Tools

859 deterministic tools in 24 categories. Free, no key needed. Each page shows the contract, an example and how to call it over MCP, HTTP or the CLI.

• Identifiers & check digits (49)
• Hashing & signatures (45)
• Money & pricing (21)
• Financial calculations (23)
• CSV & tables (47)
• Structured formats (51)
• JSON & JSONL (55)
• Text (75)
• Sequences & diffs (17)
• Dates & times (UTC, ISO 8601) (58)
• Numbers & math (157)
• Vectors & matrices (29)
• Units & sizes (23)
• Graphs & scheduling (20)
• File paths (lexical) (20)
• Forms (5)
• Encoding & checksums (33)
• URLs & IP addresses (44)
• Developer tools (14)
• Optimization & voting (6)
• Geometry, location & color (15)
• Communications (18)
• Versions & config (7)
• Other utilities (27)

Identifiers & check digits

Validate and parse bank, product, publication, transport and national identifiers with explicit coverage.

• Aba routing validate aba-routing-validate: Validate a 9-digit US ABA routing number's 3-7-1 weighted check digit and classify its 2-digit Federal Reserve prefix.
• Bic validate bic-validate: Validate a Business Identifier Code's ISO 9362:2022 structure and parse its party prefix, country, location and branch.
• Cas number validate cas-number-validate: Validate a CAS Registry Number's position-weighted mod 10 check digit over its variable-length first segment.
• Checkdigit compute checkdigit-compute: Compute the check digit(s) for a payload under a named algorithm (Luhn, Verhoeff, Damm, ISO 7064, GS1, mod 10).
• Checkdigit validate checkdigit-validate: Validate a full value's trailing check digit(s) against a named algorithm (Luhn, Verhoeff, Damm, ISO 7064, GS1, mod 10).
• Cn resident id parse cn-resident-id-parse: Parse an 18-digit (or legacy 15-digit) Chinese resident ID: region code, birth date, sex and GB 11643-1999 check digit.
• Cusip validate cusip-validate: Validate a 9-character CUSIP's Modulus 10 Double Add Double check digit and parse its issuer, issue and PPN marker.
• Doi parse doi-parse: Parse a DOI (bare, doi: or doi.org URL) into prefix, suffix, directory indicator, registrant code and canonical forms.
• Eu vat id validate eu-vat-id-validate: Detect the country from an EU/XI VAT id prefix and validate its format and, where defined, national checksum.
• Figi validate figi-validate: Validate a 12-character FIGI's structure, forbidden-prefix rule and Modulus 10 Double Add Double check digit.
• Gs1 element string parse gs1-element-string-parse: Parse a bracketed or FNC1-separated GS1 element string into typed AI fields: implied decimals, dates and check digits.
• Gs1 key validate gs1-key-validate: Validate a GTIN-8/12/13/14, GLN, SSCC or GSIN's GS1 mod-10 check digit and look up its 3-digit GS1 prefix meaning.
• Iban compute from bban iban-compute-from-bban: Compute the MOD 97-10 check digits and full IBAN for a country code and BBAN, using the pinned IBAN registry.
• Iban validate iban-validate: Validate an IBAN's country, registry length, BBAN structure and MOD 97-10 check digits, and parse its bank/branch code.
• Iccid validate iccid-validate: Validate a 19/20-digit ICCID's Luhn check digit, require the 89 major industry id, split issuer/account digits.
• Imei validate imei-validate: Validate a 15-digit IMEI's Luhn check digit or accept a 16-digit IMEISV, and split the TAC from the serial.
• Imo number validate imo-number-validate: Validate a 7-digit IMO ship identification number's weighted mod-10 check digit, with or without the 'IMO ' prefix.
• Isbn validate isbn-validate: Validate an ISBN-10 (mod 11, X allowed) or ISBN-13 (EAN mod 10) check digit and return the other form when it exists.
• Isin compute from nsin isin-compute-from-nsin: Build a 12-character ISIN from a country prefix and a CUSIP/SEDOL national number, computing its Luhn check digit.
• Isin validate isin-validate: Validate a 12-character ISIN's ISO 6166 Luhn check digit and parse its country prefix, NSIN and NSIN scheme.
• Ismn validate ismn-validate: Validate an ISMN's EAN mod 10 check digit in M-form or 979-0 form and return the canonical 13-digit form.
• Iso6346 container validate iso6346-container-validate: Validate an 11-character ISO 6346 container number's mod-11 check digit and split the owner code, category and serial.
• Issn validate issn-validate: Validate an 8-digit ISSN's mod 11 check digit (X allowed) and compute its 977-prefixed EAN-13 barcode form.
• It codice fiscale parse it-codice-fiscale-parse: Parse an Italian codice fiscale: birth date, sex, place code, check character; optionally match a surname/given name.
• Lei validate lei-validate: Validate a 20-character LEI's ISO/IEC 7064 MOD 97-10 check digits and parse its LOU prefix and entity part.
• Mx clabe validate mx-clabe-validate: Validate an 18-digit Mexican CLABE's weighted check digit and split it into bank, plaza and account fields.
• National id validate national-id-validate: Validate a personal identity number’s format and, where defined, checksum for one of 14 national schemes.
• Npi validate npi-validate: Validate a 10-digit US National Provider Identifier using the Luhn formula with the constant 80840 healthcare prefix.
• Orcid validate orcid-validate: Validate a 16-digit ORCID iD or ISNI's ISO 7064 MOD 11-2 check character, accepting bare, grouped or URL forms.
• Payment card validate payment-card-validate: Validate a payment card's Luhn check digit and detect its brand from its IIN, without returning the full number.
• Rf creditor reference compute rf-creditor-reference-compute: Compute the MOD 97-10 check digits and full ISO 11649 RF Creditor Reference for a base reference (invoice number).
• Rf creditor reference validate rf-creditor-reference-validate: Validate an RF Creditor Reference's ISO 11649 shape and MOD 97-10 check digits, and parse its base reference.
• Se personnummer parse se-personnummer-parse: Parse a Swedish personnummer/samordningsnummer: resolve its century, return birth date, sex and Luhn validity.
• Sedol validate sedol-validate: Validate a 7-character SEDOL's weighted modulus 10 check digit and report whether it is a legacy all-numeric code.
• Swiss qr reference validate swiss-qr-reference-validate: Validate a 27-digit Swiss QR-bill QR reference's modulo-10-recursive check digit and reject all-zero references.
• Tax id validate tax-id-validate: Validate a taxpayer/business registration number’s format and, where defined, checksum for one of 12 national schemes.
• Uk nhs number validate uk-nhs-number-validate: Validate a 10-digit NHS number's modulus 11 check digit (NHS Data Dictionary); 11 minus remainder = 10 is never valid.
• Ulid compare ulid-compare: Compare two canonical uppercase ULIDs by their specification-defined lexical order.
• Ulid format ulid-format: Format an explicit 48-bit timestamp and ten random bytes as one canonical uppercase ULID.
• Ulid parse canonical ulid-parse-canonical: Parse a canonical uppercase ULID into its exact timestamp, randomness, and 16 bytes.
• Ulid timestamp extract ulid-timestamp-extract: Extract the exact unsigned 48-bit millisecond timestamp from a canonical uppercase ULID.
• Upc ean convert upc-ean-convert: Convert a validated UPC-A, UPC-E, EAN-13 or GTIN-14 number to another symbol format, recomputing the check digit.
• Upu s10 validate upu-s10-validate: Validate a 13-char UPU S10 postal identifier's weighted mod-11 check digit, split service indicator and country.
• Uuid format uuid-format: Format exactly 16 octets as an RFC 9562 UUID string.
• Uuid inspect uuid-inspect: Validate a canonical UUID and report its lowercase value, variant, version, and nil status.
• Uuid parse strict uuid-parse-strict: Strictly parse one canonical lowercase RFC 9562 UUID.
• Uuid v3 generate uuid-v3-generate: Generate deterministic RFC 9562 UUIDv3 values from a namespace and UTF-8 name.
• Uuid v5 generate uuid-v5-generate: Generate deterministic RFC 9562 UUIDv5 values from a namespace and UTF-8 name.
• Vin validate vin-validate: Validate a 17-char VIN's mod-11 check digit, split WMI/VDS/VIS, and give the model-year candidates for the year code.

Hashing & signatures

Compute and verify digests, HMACs, webhook signatures, key derivation and integrity proofs.

• Adler-32 chunks verify adler32-chunks-verify: Verify that an ordered chunk list and a whole message have identical Adler-32 checksums.
• Adler-32 combine compute adler32-combine-compute: Combine two Adler-32 states without rereading either byte sequence.
• Adler-32 window roll adler32-window-roll: Roll an Adler-32 state forward by replacing one byte in a fixed-size window.
• Checksum manifest verify checksum-manifest-verify: Parse a GNU/BSD checksum manifest (sha256sum -c, tagged form) and verify caller-supplied file contents against it.
• Crc catalog check crc-catalog-check: Compare a claimed CRC with one pinned RevEng model, including CRC-12/UMTS.
• Crc catalog compute crc-catalog-compute: Compute a pinned RevEng CRC of hex bytes, including crossed-endian CRC-12/UMTS.
• Crc catalog describe crc-catalog-describe: Describe one pinned RevEng CRC model, including independent refin and refout.
• Crc catalog identify crc-catalog-identify: Identify pinned CRC RevEng algorithms that match every explicit message and check sample.
• Crc catalog list crc-catalog-list: List the pinned RevEng CRC models with check values, residues, and reflection.
• Crc check value verify crc-check-value-verify: Recompute a pinned catalogue CRC of ASCII 123456789 and compare an observed check.
• Crc parameters validate crc-parameters-validate: Validate a Rocksoft CRC parameter tuple against the pinned CRC RevEng catalogue.
• Crc parametric compute crc-parametric-compute: Compute a CRC using a named catalogue preset (CRC-8, CRC-16/ARC, CRC-32/ISO-HDLC, ...) or an explicit Rocksoft model.
• Git object id compute git-object-id-compute: Compute the Git object id git itself would give a blob, tree, commit or tag under Git's exact object framing.
• Hash digest compute hash-digest-compute: Compute a message digest (SHA-2, SHA-3, BLAKE2/3, MD5, RIPEMD-160, Keccak-256) over encoded input bytes.
• Hash digest verify hash-digest-verify: Recompute a fixed-length digest over encoded input bytes and compare it to an expected digest given in any encoding.
• Hash noncrypto compute hash-noncrypto-compute: Compute FNV-1/1a, MurmurHash3 or xxHash over encoded input bytes, with an optional seed for algorithms that take one.
• Hkdf compute hkdf-compute: Derive output key material with HKDF-Extract/Expand (RFC 5869), or HKDF-Expand alone from a caller-supplied PRK.
• Hmac compute hmac-compute: Compute HMAC-SHA256/SHA512/MD5/SHA-1/SHA-3/RIPEMD-160 (RFC 2104) over encoded key and message bytes.
• Hmac verify hmac-verify: Recompute an HMAC and compare it, constant-time, to a signature that may carry a literal prefix and be truncated.
• Ipfs cid compute ipfs-cid-compute: Compute the CIDv0, CIDv1 dag-pb and CIDv1 raw content identifiers 'ipfs add' would give a single-chunk file.
• Merkle proof verify merkle-proof-verify: Recompute a Merkle root (RFC 9162 or Bitcoin) from one leaf and its audit path, and compare it to a claimed root.
• Merkle root compute merkle-root-compute: Compute a Merkle tree root (RFC 9162 or Bitcoin) from a leaf list, with an optional audit path.
• Multihash decode multihash-decode: Strictly decode a canonical bounded hexadecimal multihash.
• Multihash digest verify multihash-digest-verify: Verify exact digest bytes and optional algorithm against a canonical multihash.
• Multihash encode multihash-encode: Encode a bounded digest as a canonical hexadecimal multihash.
• Oci descriptor verify oci-descriptor-verify: Verify supplied bytes against an OCI descriptor digest and size.
• Oci layout integrity verify oci-layout-integrity-verify: Verify an in-memory OCI image layout, index, and reachable blob closure.
• Oci manifest graph audit oci-manifest-graph-audit: Recursively audit reachable descriptors in a supplied OCI manifest graph.
• Parallelhash compute parallelhash-compute: Compute fixed-output ParallelHash128 or ParallelHash256 with an explicit bounded block size.
• Pbkdf2 compute pbkdf2-compute: Derive a key from a password and salt with PBKDF2-HMAC-SHA1/256/384/512 (RFC 8018), within a hard CPU work-unit budget.
• Sri integrity compute sri-integrity-compute: Render one or more digests of content as a W3C Subresource Integrity 'integrity' attribute value.
• Sri integrity verify sri-integrity-verify: Parse an SRI integrity attribute, check content against its strongest digest, and report which tokens were used.
• Transparency consistency verify transparency-consistency-verify: Strictly verify an RFC 9162 Certificate Transparency consistency proof.
• Transparency inclusion verify transparency-inclusion-verify: Strictly verify an RFC 9162 Certificate Transparency inclusion proof.
• Transparency root compute transparency-root-compute: Compute an RFC 9162 Certificate Transparency Merkle tree root and optional audit path.
• Tuplehash compute tuplehash-compute: Compute fixed-output TupleHash128 or TupleHash256 over an ordered tuple of byte strings.
• Tuplehash xof compute tuplehash-xof-compute: Compute TupleHashXOF128 or TupleHashXOF256 with right_encode(0) XOF framing.
• Webhook signature compute webhook-signature-compute: Compute a signed webhook header for Stripe, Slack, Standard Webhooks, Twilio, GitHub or Shopify.
• Webhook slack verify webhook-slack-verify: Verify a Slack request's X-Slack-Signature against its raw body and timestamp, with an absolute replay-window check.
• Webhook standard verify webhook-standard-verify: Verify a Standard Webhooks (Svix/Clerk/Resend) webhook-signature header against its id.timestamp.payload signing string.
• Webhook stripe verify webhook-stripe-verify: Verify a Stripe webhook's Stripe-Signature header against a raw payload, with secret-rotation and tolerance support.
• Webhook twilio verify webhook-twilio-verify: Verify a Twilio X-Twilio-Signature against a URL and form params or a JSON body, trying Twilio's port-variant URLs.
• Xxh3 128 compute xxh3-128-compute: Compute the bit-exact XXH3 128-bit hash with a uint64 seed or public 192-byte custom secret.
• Xxh3 64 compute xxh3-64-compute: Compute the bit-exact XXH3 64-bit hash with a uint64 seed or public 192-byte custom secret.
• Xxh3 vector suite verify xxh3-vector-suite-verify: Verify a bounded public suite of expected XXH3-64 and XXH3-128 known-answer vectors.

Money & pricing

Exact decimal arithmetic, rounding, allocation, taxes, invoices and supplied exchange rates.

• Currency lookup currency-lookup: Look up an ISO 4217 alphabetic or numeric currency code: name, minor-unit exponent, entities, active or withdrawn.
• Decimal divide decimal-divide: Divide two decimal strings exactly, rounding the quotient once to a fixed scale, and report the exact remainder.
• Decimal expression evaluate decimal-expression-evaluate: Evaluate a decimal arithmetic expression exactly with variables, abs, min, max and round, rounding once at the end.
• Decimal multiply decimal-multiply: Multiply two decimal strings exactly, optionally rounding the product once to a fixed scale with a chosen mode.
• Decimal power decimal-power: Raise a decimal string to an integer power exactly, with optional single rounding to a fixed scale.
• Decimal root decimal-root: Real nth root (2 to 100) of a decimal string, correctly rounded once to a fixed scale with an explicit mode.
• Decimal round decimal-round: Round a decimal string with an explicit mode to fraction digits, significant digits or a multiple of an increment.
• Decimal sum decimal-sum: Add up to 10,000 decimal strings exactly and report count, smallest and largest, with optional final rounding.
• Decimal to fraction decimal-to-fraction: Convert a decimal or repeating decimal like 0.41(6) to a reduced fraction, or the closest fraction under a cap.
• Discount stack apply discount-stack-apply: Apply an ordered stack of percent and fixed-amount discounts to a price, rounding each step or only at the end.
• Fraction to decimal expand fraction-to-decimal-expand: Expand an integer fraction into its exact decimal with the minimal repeating block marked, e.g. 1/7 as 0.(142857).
• Fx cross rate compute fx-cross-rate-compute: Derive a cross exchange rate and its inverse from two quoted rates that share one currency, at a stated scale.
• Invoice totals compute invoice-totals-compute: Compute invoice line nets, tax breakdown by rate and totals with per-line or per-rate rounding, net or gross prices.
• Money allocate money-allocate: Split a money amount by weights or into equal parts with the largest remainder method; shares sum exactly to the total.
• Money convert at rate money-convert-at-rate: Convert an amount between two ISO 4217 currencies at a caller-supplied rate with explicit quote direction and rounding.
• Money minor units convert money-minor-units-convert: Convert a decimal money amount to integer minor units (cents, fils, yen) or back, using the ISO 4217 exponent.
• Percent compute percent-compute: Exact percentage of, ratio, change, increase, decrease and reverse percentage, rounded once at a chosen scale.
• Price margin compute price-margin-compute: Solve cost, price, profit, gross margin and markup from any two of cost, price, margin percent or markup percent.
• Proration compute proration-compute: Prorate an amount by used days over period days (counts or ISO dates) into prorated and remaining parts that add up.
• Tiered price compute tiered-price-compute: Compute a total price for a quantity under graduated or volume tiers with inclusive bounds and optional flat fees.
• Vat net gross convert vat-net-gross-convert: Convert a net or gross amount at a VAT rate into a net, VAT and gross triple that adds up exactly at currency precision.

Financial calculations

Cash flows, bond yields, loan schedules, day counts and time value of money.

• Bond cashflow schedule bond-cashflow-schedule: Coupon dates, coupons remaining, accrued days and accrued interest for a regular fixed-coupon bond (Excel COUP* rules).
• Bond duration convexity bond-duration-convexity: Macaulay and modified duration, convexity and DV01 of a fixed-coupon bond at a yield (Excel DURATION, MDURATION).
• Bond price from yield bond-price-from-yield: Clean price, dirty price and accrued interest per 100 of a fixed-coupon bond from its yield (Excel PRICE, SIA).
• Bond yield from price bond-yield-from-price: Yield to maturity of a fixed-coupon bond from its clean price, with accrued and dirty price (Excel YIELD / SIA).
• Cashflow irr cashflow-irr: IRR of equally spaced cash flows with every root reported, the chosen root named and no-solution cases signalled.
• Cashflow mirr cashflow-mirr: MIRR of periodic cash flows from a finance rate and a reinvestment rate, with compounded and discounted totals.
• Cashflow npv cashflow-npv: NPV of equally spaced cash flows, time-0 or Excel time-1, with inflow PV, outflow PV and profitability index.
• Cashflow payback period cashflow-payback-period: Payback period of periodic cash flows with linear interpolation, optional discounting and the cumulative path.
• Cashflow xirr cashflow-xirr: Annual IRR of dated cash flows on the Excel XIRR 365-day basis, with all roots and the chosen root reported.
• Cashflow xnpv cashflow-xnpv: NPV of dated cash flows with the Excel XNPV 365-day exponent and an explicit valuation date.
• Daycount year fraction daycount-year-fraction: Year fraction between two ISO dates under ISDA 30/360, 30E/360, ACT/360, ACT/365F, ACT/ACT ISDA or ICMA, and NL/365.
• Dcf valuation compute dcf-valuation-compute: Enterprise and equity value from forecast free cash flows with a Gordon or exit-multiple terminal value.
• Depreciation schedule depreciation-schedule: Straight-line, sum-of-years-digits, declining-balance and Excel DB depreciation schedule that ends at salvage.
• Growth cagr compute growth-cagr-compute: CAGR from start and end values or a total return over years or dates, with a sub-year warning.
• Interest accrual compute interest-accrual-compute: Simple or compound (periodic or continuous) interest over a term in years or a dated span with a day-count basis.
• Inventory fifo period close inventory-fifo-period-close: Close a periodic FIFO inventory period with exact valuation and a balanced caller-mapped closing entry.
• Inventory fifo period reconcile inventory-fifo-period-reconcile: Reconcile reported ending inventory and COGS against an exact periodic FIFO recomputation.
• Inventory fifo periodic value inventory-fifo-periodic-value: Value ending inventory and cost of goods sold under periodic FIFO with exact, reproducible layer retention.
• Loan amortization schedule loan-amortization-schedule: Cent-exact level-payment loan schedule with per-period rounding, extra payments, dates and a row window.
• Loan apr compute loan-apr-compute: APR of an equal-payment loan net of prepaid fees under US Reg Z or the EU consumer credit directive.
• Rate nominal effective convert rate-nominal-effective-convert: Convert an interest rate between nominal (periodic compounding), effective annual and continuous compounding forms.
• Tbill yield convert tbill-yield-convert: Convert a Treasury bill price, discount rate, investment rate or money-market yield into all four (31 CFR 356 App. B).
• Tvm solve tvm-solve: Solve periods, annual rate, present value, payment or future value of a level annuity with timing and compounding.

CSV & tables

Convert, join, filter, sort, reconcile and compare CSV tables.

• CSV abs integer column csv-abs-integer-column: Replace every data cell in a named CSV column with the absolute value of a canonical integer.
• CSV add row number csv-add-row-number: Prepend a 1-based row_number column of canonical integer strings.
• CSV anti join csv-anti-join: Keep left CSV rows whose exact key tuples do not appear in the right document.
• CSV clamp integer column csv-clamp-integer-column: Clamp every data cell in a named CSV column to optional canonical integer min and max bounds.
• CSV concat csv-concat: Concatenate CSV documents that share identical headers, preserving document and row order.
• CSV dedupe csv-dedupe: Remove duplicate CSV data rows while preserving the first occurrence.
• CSV dialect detect csv-dialect-detect: Detect delimiter, quote, escape, record separator, and header for one rectangular CSV sample.
• CSV dialect format csv-dialect-format: Format string rows as CSV for an explicit dialect, quoting a one-field empty record when it can.
• CSV dialect parse csv-dialect-parse: Parse CSV with an explicit dialect into string rows, keeping leading zeros and embedded breaks.
• CSV distinct values csv-distinct-values: List distinct exact values of one CSV column in first-seen order.
• CSV drop columns csv-drop-columns: Drop named CSV columns and keep the remaining columns in original header order.
• CSV fill defaults csv-fill-defaults: Replace empty cells in named CSV columns with exact default strings.
• CSV filter compare csv-filter-compare: Filter ASCII CSV rows by string/decimal comparison; requires CRLF records, rejects LF-only and non-ASCII input.
• CSV filter empty csv-filter-empty: Keep or drop CSV rows whose named column is the empty string.
• CSV filter equals csv-filter-equals: Keep CSV data rows whose named column equals an exact string.
• CSV filter pattern literal csv-filter-pattern-literal: Filter ASCII CSV with literal contains/starts-with; requires CRLF records, rejects LF-only and non-ASCII input.
• CSV group count csv-group-count: Count CSV rows by exact named-column tuples in first-seen order.
• CSV inner join csv-inner-join: Inner join two CSV documents on exact named key columns.
• CSV left join csv-left-join: Left join two CSV documents on exact named key columns.
• CSV merge columns csv-merge-columns: Join named CSV columns with an exact separator into one column.
• CSV min max integers csv-min-max-integers: Minimum and maximum of a CSV column of strict signed base-10 integer strings.
• CSV reconcile csv-reconcile: Reconcile two CSV documents by key columns, reporting full population totals and bounded samples for added, removed, changed, invalid-key, and ambiguous rows.
• CSV rename columns csv-rename-columns: Rename CSV headers by an exact from/to mapping, preserving row cells and column order.
• CSV replace exact csv-replace-exact: Replace CSV data cells whose entire value equals an exact find string.
• CSV row diff csv-row-diff: Compare two CSV documents with identical headers by unique key tuples and report added, removed, and changed rows.
• CSV scale integer column csv-scale-integer-column: Multiply every data cell in a named CSV column by a canonical integer factor.
• CSV schema check csv-schema-check: Validate a CSV document against an ordered column list and per-column string constraints.
• CSV select columns csv-select-columns: Select and reorder exact named columns from a complete CSV document.
• CSV slice rows csv-slice-rows: Take a contiguous window of CSV data rows by offset and limit, keeping the header.
• CSV sort csv-sort: Stably sort CSV rows by exact named string columns.
• CSV split column csv-split-column: Split one CSV column on an exact separator into uniquely named columns.
• CSV sum integers csv-sum-integers: Sum a CSV column of strict signed base-10 integer strings using BigInt.
• CSV to JSON csv-to-json: Convert a complete CSV document into an array of string-valued objects.
• CSV to markdown table csv-to-markdown-table: Render ASCII CSV with CRLF records as Markdown; rejects LF-only records and non-ASCII text.
• CSV transpose csv-transpose: Transpose a CSV matrix including the header row, then re-validate headers.
• Table aggregate check table-aggregate-check: Check claimed COUNT/SUM/AVG/MIN/MAX results over JSON rows exactly (SQL nulls); returns the first mismatch.
• Table count distinct check table-count-distinct-check: Check a claimed COUNT(DISTINCT) and optional distinct-value list over JSON rows; returns the first mismatch.
• Table decimal group average table-decimal-group-average: Group table rows by string keys and compute exact decimal average results with deterministic ordering.
• Table decimal group count table-decimal-group-count: Count rows by exact string-valued dimensions with stable, bounded grouping output.
• Table decimal group cube table-decimal-group-cube: Sum exact decimal strings over deterministic SQL CUBE grouping sets with explicit subtotal markers.
• Table decimal group extrema table-decimal-group-extrema: Group table rows by string keys and compute exact decimal extrema results with deterministic ordering.
• Table decimal group rollup table-decimal-group-rollup: Sum exact decimal strings over deterministic SQL ROLLUP grouping sets with explicit subtotal markers.
• Table decimal group sum table-decimal-group-sum: Group table rows by string keys and compute exact decimal sum results with deterministic ordering.
• Table groupby check table-groupby-check: Check claimed GROUP BY rows (group keys and aggregate values) over JSON rows; returns the first wrong group or value.
• Table join count check table-join-count-check: Check a claimed inner, left, right or full equi-join row count over two JSON tables by key multiplicities.
• Table key multiplicity check table-key-multiplicity-check: Check claimed per-key row counts and join contributions for an equi-join and report the first wrong key.
• Table reconciliation check table-reconciliation-check: Check a claimed keyed reconciliation of two JSON tables and per-key statuses; report the first wrong key or count.

Structured formats

Structured data conversion and validation.

• Asn1 der encode tree asn1-der-encode-tree: Encode a schema-free ASN.1 node list as one canonical DER value.
• Asn1 der node extract asn1-der-node-extract: Extract one DER node by a numeric path, with header, content, and child paths.
• Asn1 der parse asn1-der-parse: Parse one ASN.1 DER value into a flat schema-free TLV node list.
• Asn1 der path list asn1-der-path-list: List numeric paths, offsets, lengths, and tag class for every node in one DER value.
• Asn1 der primitive decode asn1-der-primitive-decode: Decode one universal DER primitive from lowercase hex into typed fields.
• Asn1 der primitive encode asn1-der-primitive-encode: Encode one universal DER primitive from typed fields into lowercase hex.
• Asn1 der tree render asn1-der-tree-render: Render one DER value as an escaped text tree of paths, tags, lengths, and previews.
• Asn1 der validate asn1-der-validate: Check one ASN.1 DER value for canonical TLV structure and return a reason.
• Avro parsing canonical form avro-parsing-canonical-form: Produce the Avro 1.12.0 parsing canonical form for a bounded schema.
• Avro schema equivalence check avro-schema-equivalence-check: Decide whether two Avro schemas have identical Avro 1.12.0 parsing canonical forms.
• Avro schema fingerprint avro-schema-fingerprint: Compute the CRC-64-AVRO fingerprint of an Avro 1.12.0 parsing canonical form.
• Fixed width records parse fixed-width-records-parse: Parse fixed-width records with explicit offsets, widths, alignment, padding, Unicode units, and bounded diagnostics.
• Fixed width records slice fixed-width-records-slice: Slice selected fixed-width fields with explicit offsets, Unicode units, padding checks, and bounded diagnostics.
• Fixed width records validate fixed-width-records-validate: Validate fixed-width records with explicit offsets, widths, alignment, padding, Unicode units, and bounded diagnostics.
• Gitconfig format gitconfig-format: Format git config sections as canonical text with escapes and subsections.
• Gitconfig key list gitconfig-key-list: List git config keys in file order with qualified names and occurrences.
• Gitconfig parse gitconfig-parse: Parse git config text into ordered sections, subsections, and multivar entries.
• Html entities decode html-entities-decode: Decode WHATWG named and numeric HTML character references and return the resulting Unicode text.
• Html entities encode html-entities-encode: Escape text for safe insertion into HTML text or quoted attribute values and return the encoded text.
• INI to JSON ini-to-json: Convert an INI string to a JSON object.
• INI win format ini-win-format: Format sections and keys into stable Windows initialization-file text.
• INI win parse ini-win-parse: Retrieve a Windows profile string, or list section or key names, with pinned profile rules.
• INI win validate ini-win-validate: Check initialization-file text against the pinned Windows profile grammar.
• JSON to INI json-to-ini: Convert JSON data to an INI string.
• JSON to TOML json-to-toml: Convert JSON data to a TOML string.
• JSON to TSV json-to-tsv: Convert a JSON array of objects to a TSV string.
• JSON to XML json-to-xml: Convert JSON data to an XML string.
• JSON to YAML json-to-yaml: Convert JSON data to a YAML string.
• Systemd directive list systemd-directive-list: List systemd unit directives as words using syntax quoting, continuation, and resets.
• Systemd .env format systemd-env-format: Format assignments into canonical systemd EnvironmentFile text, one quoting mode per value.
• Systemd .env parse systemd-env-parse: Parse a systemd EnvironmentFile into assignments, a last-wins map, and duplicate keys.
• TOML to JSON toml-to-json: Convert a TOML string to a JSON object.
• Toml10 format toml10-format: Emit canonical TOML 1.0 source from a typed document tree.
• Toml10 parse toml10-parse: Parse TOML 1.0 into typed nodes with exact int64, floats, and datetimes.
• Toml10 validate toml10-validate: Check a TOML 1.0 document and locate the first structural error.
• TSV to JSON tsv-to-json: Convert a complete TSV document into an array of string-valued objects.
• XML exc c14n canonicalize xml-exc-c14n-canonicalize: Exclusive XML Canonicalization 1.0 of a whole document, with an optional inclusive prefix list.
• XML exc c14n subtree xml-exc-c14n-subtree: Exclusive XML Canonicalization 1.0 of one selected element and its descendants.
• XML exc c14n validate xml-exc-c14n-validate: Check whether XML is already in Exclusive XML Canonicalization 1.0 form.
• XML to JSON xml-to-json: Convert an XML string to a JSON object.
• Xpath10 boolean xpath10-boolean: Evaluate an XPath 1.0 boolean expression: comparisons, and, or, not, starts-with, contains, and boolean conversion.
• Xpath10 count xpath10-count: Count the nodes in an XPath 1.0 node-set from location paths, axes, predicates, namespaces and union.
• Xpath10 evaluate xpath10-evaluate: Evaluate an XPath 1.0 value expression and return its type with an exact string, number, or boolean token.
• Xpath10 number xpath10-number: Evaluate an XPath 1.0 numeric expression: arithmetic, div, mod, floor, ceiling, round, and number conversion.
• Xpath10 paths xpath10-paths: List the canonical XPath 1.0 path of each node in a location-path node-set, in document order.
• Xpath10 select xpath10-select: Select an XPath 1.0 node-set from location paths, axes, predicates, namespaces and union, in document order.
• Xpath10 string xpath10-string: Evaluate an XPath 1.0 expression that yields a string, including concat, substring, translate, and string conversion.
• YAML to JSON yaml-to-json: Convert a YAML string to a JSON object or array.
• Zip64 entries list zip64-entries-list: List ZIP64 central-directory entries with exact decimal-string sizes and offsets.
• Zip64 locator check zip64-locator-check: Check a ZIP64 locator and report its exact EOCD offset and disk count.
• Zip64 structure check zip64-structure-check: Check ZIP64 EOCD and central-directory structure with exact decimal-string values.

JSON & JSONL

Diff, patch, query, join, group and validate JSON documents and arrays.

• Array to JSONL array-to-jsonl: Serialize an array of JSON-safe values as JSON Lines text.
• JSON array align json-array-align: Align two JSON arrays with duplicate-safe occurrence pairs and deterministic LCS tie-breaking.
• JSON array anti join json-array-anti-join: Anti join two JSON arrays of objects on exact keys.
• JSON array concat json-array-concat: Concatenate multiple JSON arrays of objects into one.
• JSON array count json-array-count: Count structural occurrences in a JSON array in first-seen order.
• JSON array distinct by json-array-distinct-by: Deduplicate a JSON array of objects based on specific keys.
• JSON array drop keys json-array-drop-keys: Remove specific keys from each object in a JSON array.
• JSON array filter equals json-array-filter-equals: Filter JSON array objects where a key equals a specific value.
• JSON array group by json-array-group-by: Group an array of JSON objects by exact keys.
• JSON array group count json-array-group-count: Group an array of JSON objects by exact keys and return the count.
• JSON array index by json-array-index-by: Convert an array of objects into a single object indexed by a specific key.
• JSON array inner join json-array-inner-join: Inner join two JSON arrays of objects on exact keys.
• JSON array left join json-array-left-join: Left join two JSON arrays of objects on exact keys.
• JSON array merge verify json-array-merge-verify: Verify a candidate JSON array against the deterministic three-way merge result and return an exact witness.
• JSON array project json-array-project: Select specific keys from each object in a JSON array.
• JSON array rename keys json-array-rename-keys: Rename specific keys in each object in a JSON array.
• JSON array sort objects json-array-sort-objects: Stably sort an array of objects by explicit string keys using UTF-16 lexicographic order.
• JSON array three way merge json-array-three-way-merge: Merge base, left and right JSON arrays, returning deterministic output and explicit conflicting edit regions.
• JSON array unique json-array-unique: Deduplicate a JSON array by structural equality, keeping first-seen order.
• JSON candidate list json-candidate-list: Find and rank JSON object/array candidates in prose and Markdown fences (quotes and lists too) with exact raw spans.
• JSON candidate repair json-candidate-repair: Conservatively repair a JSON candidate (comments, trailing commas, truncation), log every edit and recheck RFC 8259.
• JSON canonical serialize json-canonical-serialize: Serialize a JSON value to deterministic compact text with sorted object keys and safe integers only.
• JSON deep diff json-deep-diff: Bounded deterministic JSON difference records. Not a JSON Patch implementation.
• JSON deep equal json-deep-equal: JSON-only structural equality. Object key order does not matter; array order does.
• JSON fence extract json-fence-extract: List Markdown fenced code blocks (CommonMark 0.31.2) with exact spans, unwrapped content and an RFC 8259 JSON check.
• JSON flatten json-flatten: Flatten a JSON value into a null-prototype map keyed by RFC 6901 JSON Pointers.
• JSON keyed array merge json-keyed-array-merge: Three-way merge JSON arrays by a JSON Pointer key, returning edits, moves, inserts, deletes, and conflicts.
• JSON keyed conflicts list json-keyed-conflicts-list: List deterministic content and order conflicts from a three-way JSON keyed-array comparison without resolving them.
• JSON keyed resolution apply json-keyed-resolution-apply: Apply explicit choices to every keyed-array merge conflict and return the fully reconstructed JSON array.
• JSON merge patch json-merge-patch: Apply an RFC 7396 JSON Merge Patch to a JSON value.
• JSON omit pointers json-omit-pointers: Deep-clone JSON and delete values at explicit RFC 6901 pointers.
• JSON patch apply json-patch-apply: Apply an RFC 6902 JSON Patch atomically; returns the document or the failing operation index and pointer.
• JSON patch diff json-patch-diff: Generate a deterministic RFC 6902 patch from two JSON documents; returns the ordered patch operations.
• JSON patch test only json-patch-test-only: Evaluate only RFC 6902 test operations without modifying JSON; returns each test result and whether all passed.
• JSON pick pointers json-pick-pointers: Pick cloned JSON values at explicit RFC 6901 pointers into a null-prototype map.
• JSON pointer get json-pointer-get: Return the cloned JSON value at an RFC 6901 pointer.
• JSON pointer has json-pointer-has: Return whether an RFC 6901 pointer exists as an own path.
• JSON pointer list json-pointer-list: List RFC 6901 pointers to every reachable JSON node, root first.
• JSON repair diagnose json-repair-diagnose: Classify JSON text as valid, repairable or unrepairable and locate each lexical defect and refusal by line and column.
• JSON repair map offsets json-repair-map-offsets: Map code point offsets between JSON text and its lexical repair, flagging offsets that fall inside an edit.
• JSON schema additional find json-schema-additional-find: Find every member a JSON Schema 2020-12 "additionalProperties": false forbids, with the member's JSON Pointer.
• JSON schema batch validate json-schema-batch-validate: Validate many JSON records against one Draft 2020-12 subset schema; per-record validity, error pointers, counts.
• JSON schema errors format json-schema-errors-format: Render JSON Schema output units as a 2020-12 basic or flag output document with fixed English error messages.
• JSON schema errors group json-schema-errors-group: Group batch JSON Schema errors by failing schema rule or data path; exact counts and record indexes, stable order.
• JSON schema instance locate json-schema-instance-locate: Resolve RFC 6901 instance locations (string or URI fragment) from schema errors to values, or say why they fail.
• JSON schema output validate json-schema-output-validate: Validate JSON (e.g. LLM output) against a Draft 2020-12 schema subset; returns spec output units with JSON Pointers.
• JSON schema required missing json-schema-required-missing: List every property a JSON Schema 2020-12 "required" keyword demands but the instance lacks, with JSON Pointers.
• JSON schema type mismatches json-schema-type-mismatches: List every value whose JSON type fails a JSON Schema 2020-12 "type" keyword, with expected and actual types.
• JSON schema valid items filter json-schema-valid-items-filter: Keep only the JSON records that pass (or fail) one Draft 2020-12 subset schema; returns kept records and index lists.
• JSON schema validate json-schema-validate: Validate a JSON instance against ComputeFirst Schema 1.0.
• JSON text repair json-text-repair: Repair six common lexical JSON defects (comments, trailing commas, single quotes, ...) and list every edit made.
• JSON to CSV json-to-csv: Serialize string-valued JSON rows to CSV using explicit ordered columns.
• JSON unflatten json-unflatten: Reconstruct a JSON value from a map of RFC 6901 JSON Pointers to leaves.
• JSONL to array jsonl-to-array: Parse strict JSON Lines text into an array of JSON-safe values.
• JSONL validate jsonl-validate: Validate strict JSON Lines text and report the value count and UTF-8 byte length.

Text

Compare texts, work with lines, patches, merges and Unicode details.

• Bleu brevity penalty bleu-brevity-penalty: Compute the BLEU corpus brevity penalty from candidate and reference lengths using closest reference lengths.
• Bleu corpus compute bleu-corpus-compute: Compute canonical corpus BLEU from pre-tokenized segments: score, brevity penalty, lengths, clipped n-gram counts.
• Bleu ngrams count bleu-ngrams-count: Count BLEU clipped n-gram matches and totals per order for tokenized segments, with optional clipping tables.
• Bleu sentence components bleu-sentence-components: Extract sentence BLEU statistics: clipped matches, n-gram totals, candidate and closest reference length.
• Bleu sentence compute bleu-sentence-compute: Compute sentence-level BLEU for one tokenized hypothesis with a chosen smoothing method (none or Chen-Cherry 1-3).
• Bleu smoothing compute bleu-smoothing-compute: Apply none or Chen-Cherry smoothing 1-3 to BLEU match/total counts; return smoothed counts, BP and BLEU.
• Chrf components chrf-components: Break down chrF/chrF++ into per-order n-gram counts, precision, recall and F, with configurable orders and averaging.
• Chrf compute chrf-compute: Compute exact chrF (character 6-gram F-beta, Popovic 2015) for hypothesis/reference segments, corpus and per segment.
• Chrf plus plus compute chrf-plus-plus-compute: Compute exact chrF++ (character 6-grams plus word 1-2-grams, Popovic 2017) with the word tokens it scored.
• Citation anchor check citation-anchor-check: Check a quote anchor (exact text plus prefix/suffix) matches exactly one place in a supplied source version.
• Citation batch check citation-batch-check: Check an ordered batch of citations (span+quote or quote anchors) against supplied sources; returns the first failure.
• Citation passage check citation-passage-check: Check that a cited start/end span of a supplied source version reads exactly as the quoted passage.
• Citation record dedupe citation-record-dedupe: Group duplicate CSL citation records by deterministic DOI or folded year|author|title match keys, in input order.
• Citation record key citation-record-key: Compute transparent deterministic match keys (DOI key and folded year|author|title key) for one CSL citation record.
• Citation record normalize citation-record-normalize: Normalize one CSL 1.0.2 citation record: NFC, whitespace, empty values, DOI wrapper, page dashes, dates; lists changes.
• Github heading slug github-heading-slug: Generate GitHub-style heading anchors in order, including deterministic duplicate suffix allocation.
• Jaro matches explain jaro-matches-explain: Explain the deterministic Jaro match window, paired code points, and transposition flags.
• Jaro similarity compute jaro-similarity-compute: Compute Jaro similarity with a deterministic match window and exact reduced rational audit fields.
• Jaro winkler compute jaro-winkler-compute: Compute Jaro-Winkler similarity with explicit threshold, prefix cap, and exact rational audit fields.
• Markdown sections chunk markdown-sections-chunk: Chunk a CommonMark document into sections at its top-level ATX and setext headings, with levels, paths and spans.
• Natural compare natural-compare: Compare two strings by deterministic natural order, treating ASCII digit runs numerically; returns -1, 0, or 1.
• Natural sort strings natural-sort-strings: Sort strings by natural order (file2 before file10); returns the ordered strings and standard version.
• Text apply unified patch text-apply-unified-patch: Apply a one-file unified patch to text at original line addresses with exact hunk matches.
• Text conflict parse text-conflict-parse: Parse merge or diff3 conflict-marker text into ordered text and conflict parts.
• Text conflict render text-conflict-render: Render text and conflict parts as merge or diff3 conflict-marker text.
• Text control characters find text-control-characters-find: Find non-whitespace control characters in a text string.
• Text count text-count: Count Unicode code points, UTF-16 code units, UTF-8 bytes, and lines.
• Text count words text-count-words: Count words and return their code-point average, longest word, and optional capped per-word frequencies.
• Text damerau distance text-damerau-distance: Compute bounded optimal-string-alignment distance with adjacent transpositions.
• Text delimiter chunk text-delimiter-chunk: Split text on an explicit literal delimiter (Python str.split rules, optional max_splits) with spans and line numbers.
• Text diff stats text-diff-stats: Summarize a line-record diff as keep, insert, delete, and hunk counts.
• Text edit alignment text-edit-alignment: Return a bounded optimal edit alignment with a documented deterministic tie-break order.
• Text extract between text-extract-between: Extract exact substrings between start and end markers, left to right and non-overlapping.
• Text indentation detect text-indentation-detect: Detect whether a text uses tabs or spaces for indentation by counting lines.
• Text invert unified patch text-invert-unified-patch: Invert a one-file unified patch by swapping file names and delete/insert ops.
• Text levenshtein distance text-levenshtein-distance: Compute bounded Levenshtein distance over code points or deterministic grapheme tokens.
• Text line diff text-line-diff: Diff two texts as line records, preserving each line terminator.
• Text line endings normalize text-line-endings-normalize: Normalize all line endings in a text to a specific format (LF, CRLF, or CR).
• Text lines chunk text-lines-chunk: Split parsed lines into consecutive chunks of size lines each.
• Text lines count text-lines-count: Count exact line multiplicities in first-seen order.
• Text lines difference text-lines-difference: Set difference a minus b using exact line equality.
• Text lines head text-lines-head: Return the first n parsed lines with LF reconstruction.
• Text lines intersection text-lines-intersection: Set intersection of two line sequences using exact line equality.
• Text lines multiset subtract text-lines-multiset-subtract: Multiset subtract b from a: remaining counts, first-seen order from a.
• Text lines multiset union text-lines-multiset-union: Multiset sum of two line bags: counts add, first-seen order from a then new from b.
• Text lines tail text-lines-tail: Return the last n parsed lines with LF reconstruction.
• Text lines unique text-lines-unique: Remove exact duplicate lines, keeping first-seen order.
• Text minhash cluster text-minhash-cluster: Cluster near-duplicate texts by fixed-seed MinHash signatures, with estimated Jaccard per pair.
• Text near duplicates find text-near-duplicates-find: Find every pair of texts whose exact shingle Jaccard similarity reaches a threshold, in a fixed order.
• Text NFC text-nfc: Normalize Unicode text to NFC (canonical composition).
• Text NFD text-nfd: Normalize Unicode text to NFD (canonical decomposition).
• Text paragraphs split text-paragraphs-split: Split text into paragraphs separated by blank lines (CommonMark line rules) with code point spans and line numbers.
• Text parse unified patch text-parse-unified-patch: Parse a one-file unified patch into path names and 0-based hunks.
• Text prefix suffix check text-prefix-suffix-check: Exact prefix and/or suffix boolean checks using JS string startsWith/endsWith.
• Text reading stats text-reading-stats: Return word, sentence, and paragraph counts plus a rounded-up reading-time estimate at a chosen pace.
• Text replace exact text-replace-exact: Replace exact UTF-16 substrings without regex, case folding, or Unicode normalization.
• Text run length decode text-run-length-decode: Decode canonical count:HEX; run-length text and return the expanded Unicode string.
• Text run length encode text-run-length-encode: Run-length encode Unicode text into canonical count:HEX; records and return the encoded string.
• Text sentence offsets text-sentence-offsets: Return UAX #29 sentence spans as start/end offsets in code points, UTF-16 units or UTF-8 bytes, with the ending rule.
• Text sentences chunk text-sentences-chunk: Pack whole UAX #29 sentences into chunks of at most max_size code points, UTF-16 units or UTF-8 bytes.
• Text sentences split text-sentences-split: Split text into sentences using the default Unicode UAX #29 sentence boundary rules (Unicode 17.0.0).
• Text shingle similarity text-shingle-similarity: Exact shingle-set resemblance (Jaccard) and containment of two texts, with counts and shared shingles.
• Text slice codepoints text-slice-codepoints: Slice a string by Unicode code-point indexes, not UTF-16 code units.
• Text slugify text-slugify: Create a deterministic ASCII or Unicode slug using an explicit, documented normalization profile.
• Text split exact text-split-exact: Split text on an exact literal separator and reject results that exceed max_parts.
• Text strip BOM text-strip-bom: Remove one leading U+FEFF byte-order mark from a Unicode string.
• Text tabs to spaces text-tabs-to-spaces: Convert tab characters to spaces.
• Text three way merge text-three-way-merge: Three-way merge of text line records with merge or diff3 conflict markers.
• Text trailing whitespace trim text-trailing-whitespace-trim: Remove trailing whitespace from each line in a text.
• Text unicode normalization check text-unicode-normalization-check: Check if a text string is in various Unicode normalization forms (NFC, NFD, NFKC, NFKD).
• Text unified diff text-unified-diff: Emit a one-file unified diff of two texts with comma counts and LF document breaks.
• Text weighted edit distance text-weighted-edit-distance: Compute bounded weighted insertion, deletion, and substitution distance over text tokens.
• Text word diff text-word-diff: Diff two texts as whitespace versus non-whitespace word tokens.
• Text wrap width text-wrap-width: Hard-wrap text by Unicode code-point width and return the resulting lines.
• URL safe name check url-safe-name-check: Check whether a name is a non-dot RFC 3986 unreserved ASCII URL path segment and return a reason.

Sequences & diffs

Edit scripts, longest common subsequences, hunks and three-way merges.

• Myers common subsequence myers-common-subsequence: Return a canonical indexed LCS witness derived from bounded Myers search, or null when its cap is exceeded.
• Myers diff bounded myers-diff-bounded: Produce a canonical Myers edit script within a caller distance cap, or a deterministic over-cap result.
• Myers distance bounded myers-distance-bounded: Compute Myers insert/delete distance up to a caller cap, returning null predictably when the cap is exceeded.
• Sequence apply edit script sequence-apply-edit-script: Apply a keep/delete/insert edit script to a bounded sequence with exact value matching and no fuzz.
• Sequence apply hunks sequence-apply-hunks: Apply disjoint original-address sequence hunks with exact context and no fuzz.
• Sequence compose edit scripts sequence-compose-edit-scripts: Compose two sequence edit scripts into one per-item keep/delete/insert script.
• Sequence diff hunks sequence-diff-hunks: Group a Myers sequence edit script into context hunks with 0-based original addresses.
• Sequence edit script sequence-edit-script: Compute the Myers shortest edit script between two bounded sequences, with keep/delete/insert counts.
• Sequence index map sequence-index-map: Map each left-sequence index to a kept right index, or null if deleted, and list inserted right indices.
• Sequence invert hunks sequence-invert-hunks: Invert sequence hunks by swapping delete/insert and old/new counts.
• Sequence key order check sequence-key-order-check: Check an exact stable ordering claim for bounded records by a scalar key.
• Sequence LCS sequence-lcs: Compute the longest common subsequence of two bounded sequences from the Myers shortest edit script.
• Sequence longest common substring sequence-lcsubstring: Find the longest contiguous common subarray of two bounded sequences.
• Sequence longest increasing sequence-longest-increasing: Return one longest increasing subsequence with its length, original indexes, and values.
• Sequence order check sequence-order-check: Check an exact stable ascending or descending source-index ordering claim.
• Sequence strict order check sequence-strict-order-check: Check an exact strictly ascending or descending source-index ordering claim.
• Sequence three way merge sequence-three-way-merge: Three-way merge two sequence descendants against a shared base into clean or conflict regions.

Dates & times (UTC, ISO 8601)

Add, compare, convert and bucket calendar dates, durations and UTC timestamps.

• Appointment cutoffs compute appointment-cutoffs-compute: Compute exact booking and cancellation cutoffs for an appointment from caller-supplied rules.
• Appointment request check appointment-request-check: Check an appointment request against pinned time-zone facts and caller-supplied booking rules.
• Appointment windows build appointment-windows-build: Build deterministic appointment windows from pinned time-zone facts and caller-supplied booking rules.
• Duration add duration-add: Sum mixed SI duration terms in nanoseconds and return the exact rational in a target unit.
• Duration application check duration-application-check: Check a claimed timestamp from adding or subtracting an ISO 8601 duration under explicit offset and month-end rules.
• Duration compare duration-compare: Compare two SI duration amounts after converting both to nanoseconds.
• Duration convert duration-convert: Convert a canonical integer duration between nanosecond-based SI units as an exact rational.
• Duration format clock duration-format-clock: Format a nonnegative whole or decimal second count as an exact hh:mm:ss[.fraction] clock duration.
• Duration parse clock duration-parse-clock: Parse an hh:mm:ss[.fraction] duration and return the exact nonnegative whole or decimal second count.
• ISO date add iso-date-add: Add a signed whole-day delta to a strict YYYY-MM-DD calendar date.
• ISO date add months iso-date-add-months: Add a signed month count to a YYYY-MM-DD date, clamping the day to the target month.
• ISO date add years iso-date-add-years: Add a signed whole-year delta to a YYYY-MM-DD date, clamping the day if 29 February has no match.
• ISO date age iso-date-age: Compute the calendar-aware elapsed years, months, and days between a birth date and an as-of date.
• ISO date business day add iso-date-business-day-add: Add a signed count of business days to a date, skipping caller-supplied weekend weekdays and holidays.
• ISO date business days count iso-date-business-days-count: Count the business days in an inclusive date range, skipping caller-supplied weekend weekdays and holidays.
• ISO date clamp iso-date-clamp: Clamp a YYYY-MM-DD calendar date into an inclusive [min, max] range.
• ISO date compare iso-date-compare: Compare two YYYY-MM-DD calendar dates and return -1, 0, or 1.
• ISO date day of year iso-date-day-of-year: Return the ordinal day number (1-366) of a YYYY-MM-DD date within its calendar year.
• ISO date days in month iso-date-days-in-month: Return the number of calendar days in a given proleptic Gregorian year and month.
• ISO date difference iso-date-difference: Whole days from start to end as a canonical integer string (end - start).
• ISO date from day of year iso-date-from-day-of-year: Convert a calendar year and ordinal day number (1-366) to a YYYY-MM-DD date.
• ISO date is business day iso-date-is-business-day: Test whether a date is a business day given caller-supplied weekend weekdays and holiday dates.
• ISO date is leap year iso-date-is-leap-year: Test whether a proleptic Gregorian calendar year is a leap year.
• ISO date last weekday of month iso-date-last-weekday-of-month: Return the date of the last occurrence of an ISO weekday within a calendar month.
• ISO date min max iso-date-min-max: Return the earliest and latest date in a non-empty array of YYYY-MM-DD calendar dates.
• ISO date month end iso-date-month-end: Return the last valid calendar day of the year-month of a YYYY-MM-DD date.
• ISO date month start iso-date-month-start: Return the first calendar day of the year-month of a YYYY-MM-DD date.
• ISO date next weekday iso-date-next-weekday: Return the next date on or after a given date that falls on a specified ISO weekday.
• ISO date nth weekday of month iso-date-nth-weekday-of-month: Return the date of the nth occurrence of an ISO weekday within a calendar month.
• ISO date observed shift iso-date-observed-shift: Shift a date forward or backward until it lands on a day that is neither a weekend nor a caller-supplied holiday.
• ISO date previous weekday iso-date-previous-weekday: Return the most recent date on or before a given date that falls on a specified ISO weekday.
• ISO date quarter bounds iso-date-quarter-bounds: Return the calendar quarter number and the first/last dates of the quarter containing a date.
• ISO date range contains iso-date-range-contains: Test whether an inclusive [start, end] date range contains a given date.
• ISO date range intersect iso-date-range-intersect: Compute the intersection of two inclusive [start, end] date ranges.
• ISO date range list iso-date-range-list: Enumerate the dates in an inclusive [start, end] range stepped by a whole number of days.
• ISO date range overlap iso-date-range-overlap: Test whether two inclusive [start, end] date ranges share at least one day.
• ISO date range split by month iso-date-range-split-by-month: Split an inclusive [start, end] date range into per-calendar-month sub-ranges.
• ISO date range union iso-date-range-union: Merge overlapping or day-adjacent inclusive [start, end] date ranges into the fewest equivalent ranges.
• ISO date sort iso-date-sort: Stable-sort an array of YYYY-MM-DD calendar dates.
• ISO date to week iso-date-to-week: Convert a YYYY-MM-DD calendar date to an ISO-8601 week date.
• ISO date week bounds iso-date-week-bounds: Return the Monday and Sunday of the ISO-8601 week that contains a calendar date.
• ISO date week count in year iso-date-week-count-in-year: Return the number of ISO-8601 weeks (52 or 53) in an ISO week-numbering year.
• ISO date weekday iso-date-weekday: ISO-8601 weekday number of a strict YYYY-MM-DD date (Monday=1 ... Sunday=7).
• ISO date weekday occurrences in range iso-date-weekday-occurrences-in-range: List every date within an inclusive date range that falls on a given ISO weekday.
• ISO date-time add seconds iso-datetime-add-seconds: Add a signed whole-second delta to a strict UTC ISO-8601 datetime.
• ISO date-time clamp iso-datetime-clamp: Clamp a strict UTC ISO-8601 datetime into an inclusive [min, max] range.
• ISO date-time compare iso-datetime-compare: Compare two strict UTC ISO-8601 datetimes and return -1, 0, or 1.
• ISO date-time diff seconds iso-datetime-diff-seconds: Return the signed whole-second difference between two strict UTC ISO-8601 datetimes.
• ISO date-time truncate iso-datetime-truncate: Truncate a strict UTC ISO-8601 datetime toward UTC zero at day, hour, minute, or second.
• ISO duration structure check iso-duration-structure-check: Check a claimed reading of an ISO 8601 duration: well-formedness, components and month/day/time totals.
• ISO to epoch iso-to-epoch: Convert a canonical RFC 3339 UTC timestamp to an exact integer Unix epoch count in the requested unit.
• ISO week to date iso-week-to-date: Convert an ISO-8601 week date to a YYYY-MM-DD calendar date.
• Local interval compare local-interval-compare: Normalize and compare two discrete millisecond intervals with deterministic boundary relations.
• Local interval normalize local-interval-normalize: Normalize millisecond interval endpoint conventions into a canonical half-open interval.
• Local interval resolve local-interval-resolve: Resolve a zoned local start/end pair to exact millisecond instants under explicit gap and overlap policies.
• Working hours contains working-hours-contains: Test whether an exact UTC instant is inside a versioned expanded working-hours calendar.
• Working hours expand working-hours-expand: Expand versioned weekly work schedules, overrides, closures, and DST policies into exact UTC intervals.
• Working hours total working-hours-total: Total exact elapsed seconds in a versioned working-hours calendar after DST and closure expansion.

Numbers & math

Exact math and evidence checks.

• Angle DMS convert angle-dms-convert: Convert a signed integer angle between degrees, arcminutes, and arcseconds as an exact rational.
• Array integer adjacent diff array-integer-adjacent-diff: Replace an array of canonical integer strings with consecutive first differences.
• Array integer clamp array-integer-clamp: Clamp an array of canonical integer strings to optional inclusive min and max bounds.
• Array integer cumulative sum array-integer-cumulative-sum: Replace an array of canonical integer strings with equal-length prefix sums.
• Array integer GCD array-integer-gcd: Compute the non-negative greatest common divisor of an array of canonical integer strings.
• Array integer LCM array-integer-lcm: Compute the non-negative least common multiple of an array of canonical integer strings.
• Array integer median array-integer-median: Select lower and upper middle canonical integers; emit median only for odd length.
• Array integer min max array-integer-min-max: Return the numeric minimum and maximum of canonical integer strings.
• Array integer mode array-integer-mode: Return the most frequent canonical integers, listing every mode in first-seen order.
• Array integer product array-integer-product: Multiply an array of canonical integer strings and return the canonical product.
• Array integer ranks array-integer-ranks: Assign competition (1224) ranks to canonical integers; ties share the minimum rank.
• Array integer sum array-integer-sum: Sum an array of canonical integer strings and return the canonical total.
• Array rational mean array-rational-mean: Return the reduced arithmetic mean of an array of canonical rationals.
• Array rational min max array-rational-min-max: Return the reduced numeric minimum and maximum of an array of canonical rationals.
• Array rational sum array-rational-sum: Sum an array of canonical rationals and return the reduced total.
• Assignment feasibility check assignment-feasibility-check: Check whether a claimed item-to-bin assignment is complete, unique, declared, and eligible.
• Bipartite coloring check bipartite-coloring-check: Check a complete 0/1 coloring witness for graph bipartiteness and report the first certificate discrepancy.
• Candidate key claim check candidate-key-claim-check: Check an exact candidate-key claim, including uniqueness and minimality, under an explicit SQL null policy.
• Capacity allocation check capacity-allocation-check: Check an exact claimed allocation for eligibility and per-bin decimal capacity compliance.
• Chi square decomposition check chi-square-decomposition-check: Check a claimed Pearson chi-square, its per-cell (O-E)^2/E terms and df exactly; returns the first wrong term.
• Chromatic certificate check chromatic-certificate-check: Check a claim chi(G) = k: a proper k-colouring plus a clique or bounded exhaustive proof; returns the first discrepancy.
• Cid canonical check cid-canonical-check: Check canonical CID text or binary representation and return a stable verdict.
• Classification metrics compute classification-metrics-compute: Compute exact binary-classification metrics from integer confusion-matrix counts as reduced fractions or null.
• Cnf assignment check cnf-assignment-check: Check a claimed truth assignment against a DIMACS-style CNF; report the first bad literal or unsatisfied clause.
• Coloring count check coloring-count-check: Check a proper indexed coloring and an exact canonical-decimal claim for its number of distinct colors.
• Coloring validity check coloring-validity-check: Check an indexed graph coloring certificate and report the first uncovered vertex or monochromatic edge.
• Contingency expected check contingency-expected-check: Check claimed expected counts (row total x column total / N) of a count table exactly; returns the first wrong cell.
• Contingency margins check contingency-margins-check: Check claimed row, column and grand totals of a count table exactly; returns the first wrong total.
• Correlation kendall tau correlation-kendall-tau: Compute Kendall tau-b correlation with tie correction and return a precision-rounded decimal coefficient.
• Correlation spearman correlation-spearman: Compute Spearman rank correlation with average ranks for ties and return a rounded decimal coefficient.
• Decimal add decimal-add: Exact decimal addition of canonicalizable decimal strings.
• Decimal compare decimal-compare: Compare two decimal strings exactly after canonicalization.
• Decimal subtract decimal-subtract: Exact decimal subtraction a minus b of canonicalizable decimal strings.
• Dedupe first check dedupe-first-check: Check an exact first-wins SameValueZero deduplication claim and report its first discrepancy.
• Dedupe keyed check dedupe-keyed-check: Check an exact keyed Map deduplication claim and report its first discrepancy.
• Dedupe last check dedupe-last-check: Check an exact last-wins SameValueZero deduplication claim and report its first discrepancy.
• Dimension assignment check dimension-assignment-check: Check claimed dimensions of unknown symbols make every given equation homogeneous; returns the first failure.
• Dimension equation check dimension-equation-check: Check both sides of an equation have the same dimension (optionally a claimed one); returns the first bad node or side.
• Dimension expression check dimension-expression-check: Check a formula over dimensioned symbols is consistent and has the claimed dimension; returns the first bad node.
• Directed cycle check directed-cycle-check: Check a claimed directed cycle (closed vertex list) in a digraph, or a no-cycle claim with a deterministic witness
• Fibonacci number fibonacci-number: Compute the Fibonacci number at a zero-based index and return its exact decimal string.
• Fibonacci sequence fibonacci-sequence: List exact Fibonacci numbers for an inclusive zero-based index range as decimal strings.
• Filter result check filter-result-check: Checks an exact claimed decimal filter result with source-order witnesses.
• Flow feasibility check flow-feasibility-check: Check exact integer edge capacities and flow conservation, returning the first discrepancy.
• Flow value check flow-value-check: Check a feasible exact integer flow and its claimed source value, returning the first discrepancy.
• Foreign key claim check foreign-key-claim-check: Check an exact referential-inclusion claim and first violation under an explicit composite-null policy.
• Form response check form-response-check: Report missing required answers, nulls, type failures, and choice failures.
• Graph clique check graph-clique-check: Check that listed nodes form a clique (optionally maximal, of a minimum size); returns the first missing edge.
• Graph coloring check graph-coloring-check: Check that a node colouring of an undirected graph is proper (and within k colours); returns the first conflict.
• Graph path weight check graph-path-weight-check: Check that a path of edge IDs walks source to target in a weighted digraph and sums to the claimed exact weight.
• Idna bidi check idna-bidi-check: Apply the RFC 5893 Bidi Rule to one label and name the first failing condition.
• Idna context check idna-context-check: Report every IDNA2008 CONTEXTJ and CONTEXTO finding in one mapped label.
• Integer add integer-add: Add two canonical signed integer strings and return their canonical sum.
• Integer base convert integer-base-convert: Convert a signed integer string between bases 2 and 36 using BigInt.
• Integer binomial coefficient integer-binomial-coefficient: Compute the exact binomial coefficient C(n, k), the number of ways to choose k items from n.
• Integer catalan number integer-catalan-number: Compute the nth Catalan number exactly.
• Integer compare integer-compare: Compare two canonical signed base-10 integer strings using BigInt.
• Integer CRT integer-crt: Solve a system of integer congruences (x ≡ remainder mod modulus) with the Chinese Remainder Theorem.
• Integer derangements count integer-derangements-count: Compute !n, the number of derangements (permutations with no fixed point) of n items, exactly.
• Integer digit sum integer-digit-sum: Sum the base-b digits of the magnitude of an integer string.
• Integer digital root integer-digital-root: Repeatedly sum the base-b digits of the magnitude of an integer string until a single digit remains.
• Integer divisors integer-divisors: List every positive divisor of a positive integer, ascending.
• Integer divmod integer-divmod: Integer quotient and remainder truncated toward zero.
• Integer extended GCD integer-extended-gcd: Compute the extended Euclidean algorithm result: gcd(a, b) and Bezout coefficients x, y with a*x + b*y = gcd.
• Integer factorial integer-factorial: Compute n! (n factorial) exactly for a bounded non-negative integer n.
• Integer GCD integer-gcd: Compute the non-negative greatest common divisor of two canonical integer strings.
• Integer is perfect square integer-is-perfect-square: Test whether a non-negative integer string is a perfect square.
• Integer is prime integer-is-prime: Deterministically test whether a non-negative integer string is prime.
• Integer LCM integer-lcm: Compute the non-negative least common multiple of two canonical integer strings.
• Integer mod inverse integer-mod-inverse: Compute the modular multiplicative inverse of a modulo modulus, when it exists.
• Integer mod pow integer-mod-pow: Compute base^exponent mod modulus exactly using fast modular exponentiation.
• Integer multiply integer-multiply: Multiply two canonical base-10 integer strings and return their product.
• Integer nth root integer-nth-root: Compute the exact floor of the nth root of a non-negative integer string.
• Integer permutations count integer-permutations-count: Compute the exact number of k-permutations of n distinct items, P(n, k) = n! / (n-k)!.
• Integer prime factors integer-prime-factors: Compute the prime factorization of a positive integer as a list of prime/exponent pairs.
• Integer sort integer-sort: Stable-sort canonical signed base-10 integer strings using BigInt.
• Integer sqrt integer-sqrt: Compute the exact floor of the square root of a non-negative integer string.
• Integer totient integer-totient: Compute Euler's totient function: the count of integers in [1, value] coprime to value.
• Interval contains interval_contains: Test whether a numeric interval contains a point or interval.
• Interval difference interval_difference: Compute the portion of interval a outside interval b.
• Interval intersection interval_intersection: Compute the closed intersection of two numeric intervals.
• Interval overlap interval_overlap: Test whether two numeric intervals overlap.
• Interval union interval_union: Merge overlapping or adjacent numeric intervals.
• Interval duration check interval-duration-check: Check a claimed duration between two RFC 3339 instants as exact elapsed time or as a calendar duration.
• Iso8859 europe check iso8859-europe-check: Check ISO-8859-2, -3, -4, -10, -13, or -16 using pinned published character tables.
• Iso8859 semantic check iso8859-semantic-check: Check whether every byte is defined by ISO-8859-6, ISO-8859-8, or ISO-8859-11 and report offsets.
• Join inner result check join-inner-result-check: Check a claimed ordered inner join index result and report its first discrepancy.
• Join left result check join-left-result-check: Check a claimed ordered left join index result and report its first discrepancy.
• Join semi result check join-semi-result-check: Check a claimed ordered semi-join index result and report its first discrepancy.
• Linear inconsistency certificate check linear-inconsistency-certificate-check: Check a witness y that A x = b has no solution (yA = 0, yb != 0) or no x >= 0 solution (Farkas: yA >= 0, yb < 0).
• Linear residual check linear-residual-check: Check a claimed residual r = b - A x (per component and/or its max norm) exactly for an approximate solution x.
• Linear solution check linear-solution-check: Check that a proposed solution x satisfies A x = b exactly over the rationals and report the first row that fails.
• Lp dual feasibility check lp-dual-feasibility-check: Check that LP dual multipliers satisfy y >= 0 and yA >= c exactly; return the proven upper bound y.b.
• Lp optimality certificate check lp-optimality-certificate-check: Check an LP optimum claim from a primal x and dual y: feasibility, complementary slackness and zero duality gap.
• Lp primal feasibility check lp-primal-feasibility-check: Check that a claimed LP point satisfies x >= 0 and Ax <= b exactly; report the first violated bound or row.
• Lucas number lucas-number: Compute the Lucas number at a zero-based index and return its exact decimal string.
• Maxflow certificate check maxflow-certificate-check: Check an exact max-flow/min-cut certificate and return the first deterministic discrepancy.
• Maximum flow certificate check maximum-flow-certificate-check: Check a claimed max flow with a min-cut certificate or residual search; reports the first failure or augmenting path.
• Minimum spanning tree certificate check minimum-spanning-tree-certificate-check: Check a claimed minimum spanning tree: structure, exact weight, then the cycle/cut optimality test with a swap witness
• Mixed number to rational mixed-number-to-rational: Convert a mixed number (sign, whole part, proper-fraction numerator and denominator) into a single reduced rational.
• Multiset counts check multiset-counts-check: Check an exact claimed multiplicity table for canonical JSON scalars in first-occurrence order.
• Multiset difference check multiset-difference-check: Check claimed left-only and right-only scalar bag differences in deterministic source order.
• Multiset equality check multiset-equality-check: Check whether a claimed array has exactly the same canonical JSON scalar multiplicities as a source array.
• Network cut capacity check network-cut-capacity-check: Check a claimed s-t cut: source-side membership, the edges crossing it and its capacity, with exact integers.
• Network flow feasibility check network-flow-feasibility-check: Check a claimed s-t flow for capacity bounds and conservation with exact integers; returns the first bad edge or node.
• Number engineering format number-engineering-format: Format an exact decimal in scientific or engineering notation with explicit precision and rounding.
• Number to words en number-to-words-en: Spell an integer or exact decimal in English words and return the styled text.
• Ordinal to words en ordinal-to-words-en: Spell an integer ordinal in English words and return the styled ordinal text.
• Partition result check partition-result-check: Checks both sides of a claimed stable decimal partition with source witnesses.
• Permutation indices check permutation-indices-check: Check whether claimed indices are exactly one occurrence of every source index, reporting the first discrepancy.
• Permutation ranked check permutation-ranked-check: Check exact stable ordinal ranks for decimal-string values and nulls, reporting the first source-index discrepancy.
• Permutation values check permutation-values-check: Check whether claimed values are a SameValueZero multiset permutation, reporting the first source-order discrepancy.
• Polynomial division check polynomial-division-check: Check a claimed polynomial division A = BQ + R over exact rationals: remainder degree, quotient degree, coefficients.
• Polynomial factorization check polynomial-factorization-check: Check a claimed factorization c * prod f_i^e_i of a rational polynomial: monic distinct factors, degrees, coefficients.
• Polynomial identity check polynomial-identity-check: Check a polynomial identity over exact rationals by expanding both sides; report the lowest disagreeing coefficient.
• Precedence batches check precedence-batches-check: Check whether claimed parallel batches contain every node once and respect a caller-supplied DAG.
• Precedence levels check precedence-levels-check: Check whether claimed node levels exactly equal the earliest levels induced by a caller-supplied DAG.
• Precedence order check precedence-order-check: Check whether a claimed node order is exactly a precedence-respecting linear extension of a caller-supplied DAG.
• Quota allocation check quota-allocation-check: Check an exact claimed allocation for eligibility and per-bin lower and upper quotas.
• Rational add rational-add: Add two rational numbers given as numerator/denominator integer strings and return the reduced sum.
• Rational compare rational-compare: Compare two rational numbers given as numerator/denominator integer strings by exact value.
• Rational equation check rational-equation-check: Check a chained claim like 1/2 + 1/3 = 5/6 < 1 exactly; returns the first false relation or division by zero.
• Rational expression check rational-expression-check: Check a claimed exact rational value of an integer/fraction expression; reports the true value and the difference.
• Rational multiply rational-multiply: Multiply two rational numbers given as numerator/denominator integer strings and return the reduced product.
• Rational power rational-power: Raise a rational number to an integer exponent and return the exact reduced result.
• Rational reciprocal rational-reciprocal: Invert a rational number given as a numerator/denominator integer-string pair.
• Rational simplify rational-simplify: Reduce a numerator/denominator pair to lowest terms with the sign normalized onto the numerator.
• Rational subtract rational-subtract: Subtract one rational number from another, given as numerator/denominator integer strings, and return the reduced difference.
• Rational to mixed number rational-to-mixed-number: Convert a rational number into a sign, whole part, and proper-fraction numerator/denominator.
• Rational trace check rational-trace-check: Check a step-by-step rational calculation trace; reports the first step whose operand, operator or result disagrees.
• Regex replacement check regex-replacement-check: Checks an exact claimed bounded regex replacement and reports the first differing UTF-16 index.
• Regex split check regex-split-check: Checks claimed regex split parts and separator boundaries in deterministic source order.
• Regex tokenization check regex-tokenization-check: Checks claimed regex token texts and UTF-16 spans, returning the first mismatching token.
• Regression coefficients check regression-coefficients-check: Check claimed least-squares regression coefficients against exact samples; reports rank and the first mismatch.
• Regression normal equations check regression-normal-equations-check: Check that claimed coefficients and residuals satisfy X^T e = 0 exactly; rejects singular, ambiguous designs.
• Regression residuals check regression-residuals-check: Check claimed residuals and SSE for given regression coefficients and exact samples; reports the first wrong residual.
• Resolution proof check resolution-proof-check: Check each binary resolution step (antecedents, pivot, resolvent) of a proof over a CNF; report the first bad step.
• Roman numeral convert roman-numeral-convert: Convert integers 1–3999 to canonical Roman numerals and strictly parse canonical numerals back to integers.
• Sample histogram check sample-histogram-check: Check claimed histogram counts, outside count and densities for exact edges and an edge rule; returns the first bad bin.
• Sample quantile check sample-quantile-check: Check claimed quantiles or percentiles of an exact sample under Hyndman-Fan type 1-9; returns the first mismatch.
• Sample summary check sample-summary-check: Check claimed count, sum, mean, median, range, variance or SD of an exact sample; returns the first mismatching field.
• Sat claim check sat-claim-check: Check a sat claim with a model or an unsat claim with a DRUP proof (RUP lemmas, deletions) over a CNF.
• Scc partition check scc-partition-check: Check a claimed strongly connected component partition of a digraph: coverage, reachability, maximality, order
• Shortest path certificate check shortest-path-certificate-check: Check a claimed shortest s-t path and distance in a weighted digraph using a caller-supplied potential certificate.
• Shortest path potential check shortest-path-potential-check: Check claimed single-source shortest-path distances against a weighted digraph: edge inequalities and attainment.
• Spanning tree structure check spanning-tree-structure-check: Check that claimed edge IDs form a spanning tree of a graph; reports the first missing, repeated or cyclic edge
• Spanning tree weight check spanning-tree-weight-check: Check that claimed edge IDs form a spanning tree and that their exact total weight equals the claimed weight.
• Stable sort groups check stable-sort-groups-check: Check claimed equal-key groups for exact key order, membership, and stable source order.
• Stable sort indices check stable-sort-indices-check: Check that claimed source indices are the exact ascending stable order for supplied integer keys.
• Stable sort result check stable-sort-result-check: Check that a claimed record result is the exact ascending stable sort of the supplied source records.
• Topk result check topk-result-check: Checks a claimed exact-decimal top-k ranking with deterministic source-index ties.
• Topological order check topological-order-check: Check that a claimed vertex order is a permutation and topological order of a digraph; reports the first backward edge
• Unique key claim check unique-key-claim-check: Check an exact uniqueness claim and first-duplicate certificate under an explicit SQL null policy.
• Unit conversion trace check unit-conversion-trace-check: Check a multi-step unit conversion trace with exact arithmetic; reports the first wrong step and its exact value
• Unit factor check unit-factor-check: Check a claimed conversion factor and offset between two unit expressions using caller-defined exact unit definitions
• Unit result check unit-result-check: Check a claimed converted value exactly or under declared rounding; returns the exact value and the claim error
• Utf32 check utf32-check: Check UTF-32 bytes and return a bounded diagnostic for alignment, BOM, endian, scalar, or noncharacter failure.

Vectors & matrices

Exact vector and matrix arithmetic: products, norms, determinants, inverses and linear systems.

• Matrix add matrix-add: Add two equal-shape finite-number matrices elementwise.
• Matrix determinant matrix-determinant: Compute the determinant of a small square finite-number matrix.
• Matrix hadamard matrix-hadamard: Multiply two equal-shape finite-number matrices elementwise (Hadamard product).
• Matrix identity matrix-identity: Construct the NxN identity matrix for a given size.
• Matrix inverse matrix-inverse: Compute the inverse of a small square finite-number matrix.
• Matrix multiply matrix-multiply: Multiply an MxK finite-number matrix by a KxN finite-number matrix, producing an MxN matrix.
• Matrix rank matrix-rank: Compute the numerical rank of a finite-number matrix (square or rectangular).
• Matrix scale matrix-scale: Multiply every entry of a finite-number matrix by a scalar.
• Matrix solve linear matrix-solve-linear: Solve the small square linear system A x = b for x using Gaussian elimination.
• Matrix subtract matrix-subtract: Subtract two equal-shape finite-number matrices elementwise (a minus b).
• Matrix trace matrix-trace: Compute the trace (sum of diagonal entries) of a square finite-number matrix.
• Matrix transpose matrix-transpose: Transpose an MxN finite-number matrix into an NxM matrix.
• Matrix vector multiply matrix-vector-multiply: Multiply an MxN finite-number matrix by a length-N finite-number vector, producing a length-M vector.
• Vector add vector-add: Add two equal-length finite-number vectors elementwise.
• Vector angle vector-angle: Compute the angle in radians between two equal-length finite-number vectors.
• Vector approx equal vector-approx-equal: Compare two equal-length finite-number vectors for approximate equality within an absolute tolerance.
• Vector cosine similarity vector-cosine-similarity: Return cosine similarity for two decimal-string vectors at a requested precision; reject zero vectors.
• Vector cross vector-cross: Compute the 3-dimensional cross product of two finite-number vectors.
• Vector distance vector-distance: Compute the Euclidean, Manhattan, or Chebyshev distance between two equal-length finite-number vectors.
• Vector dot vector-dot: Compute the dot (scalar) product of two equal-length finite-number vectors.
• Vector hadamard vector-hadamard: Multiply two equal-length finite-number vectors elementwise (Hadamard product).
• Vector lerp vector-lerp: Linearly interpolate (or extrapolate) between two equal-length finite-number vectors.
• Vector norm vector-norm: Compute the L1, L2 (Euclidean), or L-infinity (Chebyshev) norm of a finite-number vector.
• Vector normalize vector-normalize: Scale a finite-number vector to unit Euclidean length.
• Vector outer product vector-outer-product: Compute the outer product of two finite-number vectors, producing a matrix.
• Vector projection vector-projection: Compute the vector projection of a finite-number vector onto another.
• Vector rank by cosine vector-rank-by-cosine: Return the top matching candidate vectors by cosine score, with stable input-order ties.
• Vector scale vector-scale: Multiply every entry of a finite-number vector by a scalar.
• Vector subtract vector-subtract: Subtract two equal-length finite-number vectors elementwise (a minus b).

Units & sizes

Convert, add and compare lengths, areas, volumes, speeds, pressures, temperatures and byte sizes.

• Area unit convert area-unit-convert: Convert an exact decimal area among ten SI, imperial, acre, and hectare units using pinned rational factors.
• Byte size add bytesize-add: Add non-negative integer byte-size terms in mixed IEC units and return the exact sum in a chosen unit.
• Byte size compare bytesize-compare: Compare two non-negative integer byte sizes by exact byte amounts.
• Byte size convert bytesize-convert: Convert a non-negative integer byte size between IEC binary units as an exact rational.
• Css length convert css-length-convert: Convert px, pt, pc, in, cm, mm, or Q using exact CSS ratios; returns a rounded decimal value.
• Css px to rem css-px-to-rem: Convert px to rem or em with a supplied root or parent font size; returns an exactly rounded relative length.
• Css rem to px css-rem-to-px: Convert rem or em to px using a supplied root or parent font size; returns an exactly rounded pixel length.
• Ideal gas state solve ideal-gas-state-solve: Solve one missing ideal-gas state variable from exact decimal SI inputs using the pinned 2019 SI gas constant.
• Length add length-add: Add integer length terms in mixed units and return the exact sum in a chosen unit.
• Length compare length-compare: Compare two integer length measurements by exact nanometer amounts.
• Length convert length-convert: Convert a canonical integer length between exact SI and international customary units.
• Mass add mass-add: Add mixed-unit canonical integer mass amounts and express the sum in a target unit as a reduced rational.
• Mass compare mass-compare: Compare two mixed-unit canonical integer mass amounts using exact nanogram BigInt values.
• Mass convert mass-convert: Convert a canonical integer mass amount between exact nanogram-based units as a reduced rational.
• Plane stress transform plane-stress-transform: Transform a plane-stress state and return ordered in-plane principal stresses, shear, and orientation.
• Pressure unit convert pressure-unit-convert: Convert exact decimal pressure values among seven units and return a reduced exact fraction.
• Speed unit convert speed-unit-convert: Convert an exact decimal speed among metres per second, kilometres per hour, mph, knots, and feet per second.
• Strain rosette compute strain-rosette-compute: Reduce a rectangular 0°/45°/90° strain rosette to tensor components and ordered principal strains.
• Temperature compare temperature-compare: Compare two temperatures in C, F, or K by converting both to Kelvin rationals.
• Temperature convert temperature-convert: Convert a decimal temperature between Celsius, Fahrenheit, and Kelvin as an exact rational.
• Uniaxial stress compute uniaxial-stress-compute: Compute axial engineering stress and strain from unit-bearing force, area, elongation, and original length.
• Volume unit convert volume-unit-convert: Convert exact decimal volumes among SI, cubic, US liquid, and imperial units with explicit half-even rounding.
• Von mises stress compute von-mises-stress-compute: Compute the three-dimensional von Mises equivalent stress from normal and tensor shear stress components.

Graphs & scheduling

Topological sort, cycles, paths, reachability and task schedules.

• Graph ancestors graph-ancestors: List every ancestor of given targets, including the targets, in reverse-graph BFS discovery order.
• Graph connected components graph-connected-components: Partition a directed simple graph into undirected connected components, ignoring edge direction.
• Graph DAG longest path graph-dag-longest-path: Return a longest node-weighted path in a DAG, where path weight is the sum of node durations.
• Graph dependency impact graph-dependency-impact: List nodes downstream of a removed set: not themselves removed, reachable by a directed path of length at least 1.
• Graph find cycle graph-find-cycle: Find one directed cycle by 3-color DFS, or report that the graph is acyclic.
• Graph from adjacency graph-from-adjacency: Rebuild a simple directed graph from adjacency lists of node ids and successors.
• Graph induced subgraph graph-induced-subgraph: Return the vertex-induced subgraph on a listed node subset, preserving declared node and edge order.
• Graph reachable from graph-reachable-from: List nodes reachable from given sources by directed BFS, in discovery order.
• Graph reverse graph-reverse: Reverse every directed edge of a simple graph, keeping node order and original edge order.
• Graph shortest unweighted path graph-shortest-unweighted-path: Find a shortest directed path by fewest edges from source to target.
• Graph strongly connected components graph-strongly-connected-components: Partition a directed simple graph into strongly connected components, listed by declared node index.
• Graph to adjacency graph-to-adjacency: Convert a directed simple graph into per-node outgoing adjacency lists.
• Graph topological sort graph-topological-sort: Return a Kahn topological order of a directed acyclic graph, breaking ready-set ties by declared node index.
• Graph transitive closure graph-transitive-closure: List directed reachability pairs of path length at least 1, ordered by declared node index.
• Graph transitive reduction graph-transitive-reduction: Compute the transitive reduction of a DAG: keep an edge u→v iff the original graph has no directed path from u to v of length at least 2.
• Graph validate graph-validate: Inspect a well-formed directed simple graph and report counts, isolated nodes, and maximum degrees.
• Schedule ASAP layers schedule-asap-layers: Partition a DAG into ASAP topological generations: each layer is the nodes that become ready together.
• Schedule critical path schedule-critical-path: Compute CPM zero-slack critical nodes and tight edges on a DAG, plus one representative critical path.
• Schedule earliest finish schedule-earliest-finish: Compute CPM earliest start and earliest finish times for a DAG with node durations, plus the project makespan.
• Schedule ready nodes schedule-ready-nodes: List DAG nodes that can start because they are not completed and every predecessor is completed.

File paths (lexical)

Normalize, join, match and group path strings without touching a filesystem.

• Path format convert path-format-convert: Convert file paths between POSIX and Windows formats, handling slashes, drive letters, and roots lexically.
• Path lexical common ancestor path-lexical-common-ancestor: Compute the deepest common ancestor directory of a set of paths.
• Path lexical contains path-lexical-contains: Check whether a child path is lexically inside a parent directory.
• Path lexical join path-lexical-join: Join an array of path segments lexically, resolving absolute reset boundaries and normalizing separators.
• Path lexical normalize path-lexical-normalize: Normalize a path lexically: collapse redundant separators, resolve "." and ".." segments.
• Path lexical parse path-lexical-parse: Decompose a file path into its lexical components without accessing the filesystem.
• Path lexical relative path-lexical-relative: Compute the lexical relative path from one path to another without filesystem access.
• Path lexical sanitize path-lexical-sanitize: Sanitize an untrusted path to produce a safe relative path, stripping roots, drive letters, traversal segments, and illegal characters.
• Path set classify path-set-classify: Classify an array of file paths by file extension, depth histogram, and path format.
• Path set dedupe path-set-dedupe: Deduplicate an array of paths based on lexical equivalence while preserving first or last seen order.
• Path set difference path-set-difference: Compute the set difference (A \ B) of two path collections using lexical path equivalence.
• Path set glob filter path-set-glob-filter: Filter an array of paths against glob patterns with inclusion and exclusion rules lexically without filesystem access.
• Path set glob test path-set-glob-test: Test a single path string against glob patterns lexically and return match disposition and matching pattern.
• Path set hierarchy tree path-set-hierarchy-tree: Transform a flat array of file paths into a nested deterministic directory tree structure.
• Path set ignore filter path-set-ignore-filter: Filter paths against gitignore-style rule lines (negation, comments, directory trailing slashes) lexically.
• Path set intersection path-set-intersection: Compute the set intersection of multiple path collections using lexical path equivalence.
• Path set minimal covering path-set-minimal-covering: Find the minimal covering set of paths by collapsing child paths when an ancestor path is already in the set.
• Path set partition directory path-set-partition-directory: Partition an array of file paths into buckets grouped by parent directory or directory at a specified depth.
• Path set prefix strip path-set-prefix-strip: Strip a common directory prefix or base path from an array of paths lexically.
• Path set union path-set-union: Compute the set union of multiple path collections, normalized and deterministically sorted.

Forms

Compare form definitions, answers and response sets.

• Form answer diff form-answer-diff: Diff two answer maps against one shared form definition.
• Form compare form-compare: Compare two filled form snapshots and return compact field and answer changes.
• Form definition diff form-definition-diff: Diff two form definitions by stable field id, including choice lists and field order.
• Form field map form-field-map: Rename form fields with an explicit id map and reject collisions.
• Form response diff form-response-diff: Reconcile two form response sets by exact respondent id.

Encoding & checksums

Base encodings, UTF-8, hex bytes, varints and non-cryptographic checksums.

• Adler-32 adler32: Adler-32 of UTF-8 bytes (RFC 1950). Integrity check only; no security claim.
• Asn1 oid format asn1-oid-format: Format numeric object identifier arcs as dotted text or brace notation.
• Asn1 oid parse asn1-oid-parse: Parse an X.680 object identifier value into numeric arcs and dotted form.
• Base64 UTF-8 base64-utf8: Decode standard Base64 to UTF-8 text. Transformation only; no security claim.
• Bech32 convert bits bech32-convert-bits: Regroup integers between bit widths using BIP 173 rules, rejecting bad leftover padding.
• Bech32 decode bech32-decode: Decode Bech32 or Bech32m text into a lowercase HRP, 5-bit data, and the checksum variant.
• Bech32 encode bech32-encode: Encode lowercase HRP and 5-bit data as Bech32 or Bech32m text using that checksum.
• Bech32 validate bech32-validate: Check Bech32 or Bech32m text and return a reason, without throwing when the checksum fails.
• Cid parse cid-parse: Parse a CIDv0 or CIDv1 envelope without hashing content.
• Cid version convert cid-version-convert: Convert permitted CIDv0 and CIDv1 envelopes without recomputing their multihash.
• CRC-32 crc32: CRC-32 of UTF-8 bytes (ISO 3309 / ZIP / PNG polynomial). Integrity check only; no security claim.
• Ct consistency proof verify ct-consistency-proof-verify: Strictly verify an RFC 6962 v1 append-only consistency proof.
• Ct inclusion proof verify ct-inclusion-proof-verify: Strictly verify an RFC 6962 v1 Merkle audit path.
• Ct merkle root compute ct-merkle-root-compute: Compute the RFC 6962 v1 domain-separated Merkle Tree Hash of raw leaves.
• Hex bytes concat hex-bytes-concat: Concatenate a bounded ordered list of lowercase hex byte strings into one hex string.
• Hex bytes slice hex-bytes-slice: Slice a lowercase hex byte string by explicit byte-index bounds, half-open like Array.slice.
• Hex bytes xor hex-bytes-xor: Byte-wise XOR of two equal-length lowercase hex byte strings. Transformation only; no cryptographic security claim.
• Iso8859 europe decode iso8859-europe-decode: Decode ISO-8859-2, -3, -4, -10, -13, or -16 using pinned published character tables.
• Iso8859 europe encode iso8859-europe-encode: Encode ISO-8859-2, -3, -4, -10, -13, or -16 using pinned published character tables.
• Iso8859 semantic decode iso8859-semantic-decode: Decode ISO-8859-6 Arabic, ISO-8859-8 Hebrew, or ISO-8859-11 Thai bytes into logical Unicode text.
• Iso8859 semantic encode iso8859-semantic-encode: Encode logical Unicode text as ISO-8859-6 Arabic, ISO-8859-8 Hebrew, or ISO-8859-11 Thai bytes.
• Pem envelope format pem-envelope-format: Format a label and lowercase hex bytes as a canonical RFC 7468 PEM envelope.
• Pem envelope parse pem-envelope-parse: Parse one RFC 7468 textual envelope into its label and lowercase hex bytes.
• Pem envelope validate pem-envelope-validate: Check one RFC 7468 PEM envelope for labels, whitespace, and strict base64.
• Pem label validate pem-label-validate: Check a PEM label against the RFC 7468 label grammar, without reading a payload.
• Segwit address decode segwit-address-decode: Decode a native segwit address into witness version, program hex, and script pubkey.
• Segwit address encode segwit-address-encode: Encode a witness program as a native segwit address using Bech32 for v0 and Bech32m for v1-v16.
• Segwit address validate segwit-address-validate: Validate a native segwit address and report which Bech32 or Bech32m rule failed.
• Utf32 BOM inspect utf32-bom-inspect: Inspect base64 bytes for UTF-32 alignment and a UTF-32LE or UTF-32BE byte-order mark without guessing.
• Utf32 decode utf32-decode: Decode strict base64 UTF-32LE or UTF-32BE bytes after BOM, alignment, scalar, and noncharacter validation.
• Utf32 encode utf32-encode: Encode Unicode scalar text as bit-exact UTF-32LE or UTF-32BE base64 bytes with an optional BOM.
• UTF-8 Base64 utf8-base64: Encode a Unicode string as standard Base64 of its UTF-8 bytes. Transformation only; no security claim.
• UTF-8 hex utf8-hex: Encode a Unicode string as lowercase hex of its UTF-8 bytes. Transformation only; no security claim.

URLs & IP addresses

Parse, build and normalize URLs and query strings; IPv4 and IPv6 addresses, CIDR blocks and subnets.

• Idna domain diagnose idna-domain-diagnose: Validate each dot-separated IDNA2008 label and the 253-octet DNS wire length.
• Idna domain map idna-domain-map: Map a domain with the Unicode 17 UTS #46 table, steps 1 and 2 only.
• Idna domain to ascii idna-domain-to-ascii: Convert a domain to DNS ASCII with UTS #46 ToASCII, STD3, and DNS lengths.
• Idna domain to unicode idna-domain-to-unicode: Convert a domain to Unicode with UTS #46 ToUnicode and decode A-labels.
• Idna label validate idna-label-validate: Validate one already-mapped IDNA2008 label for registration or lookup.
• IPv4 address classify ipv4-address-classify: Classify an IPv4 address against the static IANA IPv4 special-purpose address registry.
• IPv4 address compare ipv4-address-compare: Compare two canonical IPv4 addresses by their numeric uint32 value.
• IPv4 address distance ipv4-address-distance: Compute the signed integer distance between two IPv4 addresses (address_b minus address_a).
• IPv4 address offset ipv4-address-offset: Add a signed integer offset to an IPv4 address, throwing if the result leaves the IPv4 address space.
• IPv4 CIDR aggregate ipv4-cidr-aggregate: Merge a list of IPv4 CIDR blocks into the minimal equivalent list of non-overlapping CIDR blocks.
• IPv4 CIDR contains ipv4-cidr-contains: Test whether one IPv4 CIDR block fully contains another IPv4 CIDR block.
• IPv4 CIDR overlap ipv4-cidr-overlap: Test whether two IPv4 CIDR blocks overlap (share at least one address).
• IPv4 CIDR parse ipv4-cidr-parse: Parse an IPv4 CIDR block into its network, broadcast, netmask, wildcard mask, usable host range and address counts.
• IPv4 CIDR subnets ipv4-cidr-subnets: Split an IPv4 CIDR block into the full ordered list of equal-size subnets at a given longer prefix.
• IPv4 format ipv4-format: Format a uint32 integer string or four octets as a canonical dotted-decimal IPv4 address.
• IPv4 in CIDR ipv4-in-cidr: Test whether a canonical IPv4 address lies in a CIDR prefix whose host bits are zero.
• IPv4 mask convert ipv4-mask-convert: Convert between an IPv4 prefix length, dotted subnet netmask, and dotted wildcard (host) mask.
• IPv4 parse ipv4-parse: Parse a canonical dotted-decimal IPv4 address into octets and a uint32 integer string.
• IPv4 prefix for hosts ipv4-prefix-for-hosts: Compute the smallest IPv4 CIDR block (largest prefix length) whose usable host capacity meets a required count.
• IPv4 prefix set equal ipv4-prefix-set-equal: Report whether two IPv4 prefix sets cover exactly the same addresses.
• IPv4 prefix set intersect ipv4-prefix-set-intersect: Intersect two IPv4 prefix sets into one sorted minimal list of disjoint CIDRs.
• IPv4 prefix set subtract ipv4-prefix-set-subtract: Subtract one IPv4 prefix set from another into sorted minimal disjoint CIDRs.
• IPv4 prefix set union ipv4-prefix-set-union: Union two IPv4 prefix sets into one sorted minimal list of disjoint CIDRs.
• IPv4 range to cidrs ipv4-range-to-cidrs: Convert an arbitrary IPv4 address range into the minimal list of CIDR blocks that exactly covers it.
• IPv6 address classify ipv6-address-classify: Classify an IPv6 address against the static IANA IPv6 special-purpose address registry.
• IPv6 address compare ipv6-address-compare: Compare two IPv6 addresses by their numeric 128-bit value.
• IPv6 address distance ipv6-address-distance: Compute the signed integer distance between two IPv6 addresses (address_b minus address_a).
• IPv6 address offset ipv6-address-offset: Add a signed integer offset to an IPv6 address, throwing if the result leaves the IPv6 address space.
• IPv6 CIDR aggregate ipv6-cidr-aggregate: Merge a list of IPv6 CIDR blocks into the minimal equivalent list of non-overlapping CIDR blocks.
• IPv6 CIDR contains ipv6-cidr-contains: Test whether one IPv6 CIDR block fully contains another IPv6 CIDR block.
• IPv6 CIDR overlap ipv6-cidr-overlap: Test whether two IPv6 CIDR blocks overlap (share at least one address).
• IPv6 CIDR parse ipv6-cidr-parse: Parse an IPv6 CIDR block into its canonical network address, prefix, first/last address, and total address count.
• IPv6 CIDR subnets ipv6-cidr-subnets: Split an IPv6 CIDR block into the full ordered list of equal-size subnets at a given longer prefix.
• IPv6 format ipv6-format: Format 8 hextets or a 128-bit integer string as the RFC 5952 canonical compressed IPv6 address.
• IPv6 in CIDR ipv6-in-cidr: Test whether an IPv6 address lies in a CIDR prefix whose host bits are zero.
• IPv6 IPv4 mapped ipv6-ipv4-mapped: Convert between an IPv4 address and its IPv4-mapped IPv6 form (::ffff:0:0/96), in either direction.
• IPv6 normalize ipv6-normalize: Normalize any valid textual IPv6 address directly into its RFC 5952 canonical compressed string.
• IPv6 parse ipv6-parse: Parse an IPv6 address (any RFC 4291 textual form) into its 8 hextets and a 128-bit integer string.
• IPv6 range to cidrs ipv6-range-to-cidrs: Convert an arbitrary IPv6 address range into the minimal list of CIDR blocks that exactly covers it.
• URL normalize url-normalize: Normalize an absolute http or https URL via WHATWG parse. No DNS, fetch, or security-equivalence claim.
• URL query build url-query-build: Build a query string or replace an absolute URL query from ordered pairs. No fetching.
• URL query merge url-query-merge: Merge query pairs into an absolute URL. No fetching.
• URL query parse url-query-parse: Parse query pairs and fragment from an absolute URL. Parse only; no fetching.
• URL resolve url-resolve: Resolve a URL against an absolute http(s) base using WHATWG. No fetching. Result must be http(s).

Developer tools

Inspect developer protocols, configuration, SQL statements and command-line representations.

• Chmod mode convert chmod-mode-convert: Convert a Unix permission mode and apply explicit chmod symbolic clauses, returning canonical octal and symbolic forms.
• Commit conventional parse commit-conventional-parse: Parse one Conventional Commits 1.0.0 message into its header, body, footers, and breaking-change status.
• Editorconfig resolve editorconfig-resolve: Resolve EditorConfig properties for one normalized relative POSIX path from caller-supplied file contents.
• Git copies detect git-copies-detect: Detect deterministic Git-style copy pairs while allowing one source to match multiple destinations.
• Git rename score git-rename-score: Score Git-style line-chunk content similarity as an exact integer percentage with byte evidence.
• Git renames detect git-renames-detect: Detect deterministic one-to-one Git-style rename pairs, unmatched paths, scores, and byte evidence.
• Har summarize har-summarize: Summarize a HAR 1.2 JSON log into deterministic request, status, MIME, host, timing, size, and redaction counts.
• Mustache template render mustache-template-render: Render a logic-less Mustache template (spec v1.4.2) with JSON data and inline partials; returns the exact text.
• Mustache template validate mustache-template-validate: Check Mustache template syntax (spec v1.4.2) and its partials; returns valid or the first error with line and column.
• Mustache variables list mustache-variables-list: List the names and partials a Mustache template references, with tag kind, line, column and enclosing sections.
• Openapi operation extract openapi-operation-extract: Extract one OpenAPI operation, merge inherited parameters, and return its local component-reference closure.
• Shell argv quote shell-argv-quote: Quote inert argv strings for POSIX sh or PowerShell 7, returning a command and its per-argument fragments.
• Sql statements split sql-statements-split: Split SQL text into exact statement spans with explicit PostgreSQL, MySQL, or SQLite lexical rules.
• Tap output parse tap-output-parse: Parse TAP version 13 text into ordered assertions, plan validity, diagnostics, directives, and bailout state.

Optimization & voting

Solve bounded optimization, assignment, scheduling, voting and Pareto-front problems.

• Assignment hungarian solve assignment-hungarian-solve: Solve a bounded rectangular integer minimum-cost assignment with explicit unmatched costs.
• Knapsack 01 solve knapsack-01-solve: Solve bounded 0/1 knapsack exactly and return the optimum value, weight, and lexicographically smallest index list.
• Pareto front find pareto-front-find: Find stable nondominated row indices and a domination witness for every excluded row using exact rational criteria.
• Rank borda aggregate rank-borda-aggregate: Aggregate weighted complete or partial rankings into exact Borda scores, rank groups, and audit contributions.
• Round robin schedule generate round-robin-schedule-generate: Generate a deterministic single or double round-robin schedule with ordered rounds, home/away assignments, and byes.
• Vote condorcet winner vote-condorcet-winner: Compute weighted pairwise counts, a strict Condorcet winner, and the generalized Smith set.

Geometry, location & color

Measure and classify polygons, geohashes and accessible color contrast.

• Affine2d apply affine2d-apply: Apply one exact rational 2D affine map to bounded points or free vectors.
• Affine2d compose affine2d-compose: Compose two exact rational 2D affine maps in first-then-second order.
• Affine2d fixed set affine2d-fixed-set: Classify and compute the exact fixed locus of a rational 2D affine map.
• Affine2d invert affine2d-invert: Invert a nonsingular exact rational 2D affine map with canonical output.
• Color adjust lightness color-adjust-lightness: Lightens or darkens a CSS color by percentage points of HSL lightness and returns a hex color.
• Color contrast wcag color-contrast-wcag: Compute WCAG 2.x relative luminance, contrast ratio, and AA/AAA pass flags for two opaque sRGB colors.
• Color convert color-convert: Converts hex, rgb(), hsl(), or hwb() colors and returns the requested normalized notation.
• Geo destination point geo-destination-point: Compute the spherical destination from a start point, initial bearing, and distance; return latitude and longitude.
• Geo haversine distance geo-haversine-distance: Compute the spherical great-circle distance between two latitude/longitude points and return it in the requested unit.
• Geo initial bearing geo-initial-bearing: Compute the initial spherical bearing from point A to point B and return degrees clockwise from true north.
• Homography apply homography-apply: Apply an exact 2D homography to a homogeneous point or line, including points at infinity.
• Homography compose homography-compose: Compose two exact 2D homographies and return a canonical projective matrix.
• Homography incidence verify homography-incidence-verify: Verify exact point-line incidence before and after a 2D homography with certificates.
• Homography invert homography-invert: Invert an exact nonsingular 2D homography and return a canonical projective matrix.
• Point in polygon classify point-in-polygon-classify: Classifies a rational-coordinate point as inside, outside, or boundary using an exact half-open ray rule.

Communications

Messages, DNS wire data and email addresses.

• Dns class code lookup dns-class-code-lookup: Look up a pinned DNS class mnemonic or its numeric code.
• Dns header flags explain dns-header-flags-explain: Explain an RFC 1035 DNS header flags word, with reserved Z as an integer 0 through 7.
• Dns message encode dns-message-encode: Encode a structured DNS message to canonical uncompressed RFC 1035 wire hex.
• Dns message parse dns-message-parse: Parse a DNS message hex string into the RFC 1035 header, questions, and resource records.
• Dns message validate dns-message-validate: Validate DNS message hex structure: counts, names, compression, and OPT records.
• Dns rdata decode dns-rdata-decode: Decode DNS RDATA hex for A, AAAA, NS, CNAME, PTR, MX, TXT, SOA, SRV, or unknown.
• Dns rdata encode dns-rdata-encode: Encode DNS RDATA for A, AAAA, NS, CNAME, PTR, MX, TXT, SOA, SRV, or unknown hex.
• Dns type code lookup dns-type-code-lookup: Look up a pinned DNS RR type mnemonic or its numeric code.
• Email address list deduplicate email-address-list-deduplicate: Drop duplicate mailboxes in an RFC 5322 address-list, keeping the first one.
• Email address list format email-address-list-format: Format mailboxes and groups as one deterministic RFC 5322 address-list.
• Email address list parse email-address-list-parse: Parse an RFC 5322 address-list into ordered mailboxes, groups, and a canonical form.
• Email address list validate email-address-list-validate: Check RFC 5322 address-list syntax, including dots, quotes, comments, and groups.
• Email address normalize email-address-normalize: Validate one email addr-spec and return its canonical form: minimal quoting, NFC local-part, lowercase domain.
• Email address spans email-address-spans: Locate every email address occurrence in text with exact half-open code point, UTF-16 and UTF-8 offsets.
• Email addresses extract email-addresses-extract: Extract the unique email addresses (RFC 5322 addr-spec subset) from text, normalized, in first-seen order.
• Email mailbox format email-mailbox-format: Render a canonical RFC 5322 mailbox from decoded parts, without a delivery claim.
• Email mailbox parse email-mailbox-parse: Parse one RFC 5322 mailbox into parts and canonical text, without a delivery claim.
• Email mailbox validate email-mailbox-validate: Check one RFC 5322 mailbox for syntax only and return a stable reason code.

Versions & config

Semantic version ranges and sorting; .env parsing and merging.

• .env merge env-merge: Overlay two dotenv-subset documents, replacing left values and appending right-only keys.
• .env parse env-parse: Parse a strict dotenv-subset document into ordered key/value entries.
• .env stringify env-stringify: Serialize unique env key/value entries to a canonical dotenv-subset document.
• SemVer compare semver-compare: Compare two strict Semantic Versions by precedence.
• SemVer filter semver-filter: Filter strict versions that satisfy a range, preserving original order and strings.
• SemVer satisfies semver-satisfies: Test whether a strict version satisfies a semver range.
• SemVer sort semver-sort: Sort strict valid Semantic Versions in ascending precedence order.

Other utilities

More deterministic helpers.

• Array duplicates find array-duplicates-find: List duplicated JSON values with counts and first indexes, preserving first-seen order.
• Array set difference array-set-difference: Return unique left-array values absent from the right array, in first-seen order.
• Array set intersection array-set-intersection: Return unique left-array values also in the right array, in first-seen order.
• Base64url decode base64url-decode: Decode base64url to UTF-8 text or lowercase hex and return the requested value.
• Base64url encode base64url-encode: Encode supplied UTF-8 text or hexadecimal bytes as base64url and return the encoded string.
• Base64url validate base64url-validate: Check canonical base64url syntax and return validity plus the first invalid character when present.
• Bytes format human bytes-format-human: Format an exact byte count as both SI and IEC strings and return the rounding mode used.
• Bytes parse human bytes-parse-human: Parse an SI or IEC byte-size string and return an exact integer byte count using explicit rounding.
• Cron describe fields cron-describe-fields: Parse a five-field cron expression and return each field’s expanded numeric values and wildcard status.
• Cron expression validate cron-expression-validate: Check whether a five-field cron expression is supported and return a validity flag with a reason code.
• Cron next runs cron-next-runs: Compute the next requested UTC fire times for a five-field cron schedule and echo the supplied reference instant.
• Cron previous runs cron-previous-runs: Compute the previous requested UTC fire times for a five-field cron schedule and echo the supplied reference instant.
• Data rate convert data-rate-convert: Convert bit or byte rates across SI and IEC prefixes and return an exact reduced rational.
• Epoch to ISO epoch-to-iso: Convert an exact integer Unix timestamp in seconds, milliseconds, microseconds or nanoseconds to RFC 3339 UTC.
• Geohash convert geohash-convert: Encode decimal coordinates as a bounded Geohash or decode a Geohash to its exact bounding box and midpoint.
• Hebrew civil date convert hebrew-civil-date-convert: Convert dates between proleptic Gregorian calendar and civil Hebrew calendar
• Html to plain text html-to-plain-text: Strip HTML and script/style text, decode supported references; collapse whitespace including inside pre elements.
• Identifier case convert identifier-case-convert: Convert an ASCII identifier to a requested common case and return the converted identifier.
• Polygon measures compute polygon-measures-compute: Compute exact signed double-area, area, orientation, and squared edge lengths for a rational simple polygon.
• Rtf inspect rtf-inspect: Inspect an 8 KiB ANSI-1252 RTF text subset: paragraphs, omitted destinations, pictures, objects and warnings.
• Rtf to markdown rtf-to-markdown: Convert an 8 KiB ANSI-1252 RTF text subset to escaped Markdown; unsupported Word features are refused.
• Stats describe exact stats-describe-exact: Return exact descriptive statistics and requested-precision standard deviations for decimal strings.
• Stats histogram stats-histogram: Count decimal-string values in caller-supplied fixed bins and return below- and above-range totals.
• Stats percentile stats-percentile: Compute an exact percentile from decimal strings using a named Hyndman-Fan type 1 through 9.
• Xlsx inspect xlsx-inspect: inspect excel workbook structure.
• Xlsx to CSV xlsx-to-csv: convert excel sheet to csv.
• Xlsx to markdown xlsx-to-markdown: convert excel workbook to markdown.