Tools

350 deterministic tools in 15 categories. Free, no key needed. Each page shows the contract, an example and how to call it over MCP, HTTP or the CLI.

• CSV & tables (29)
• YAML, TOML, INI, XML & TSV (10)
• JSON & JSONL (31)
• Text (34)
• Sequences & diffs (10)
• Dates & times (UTC, ISO 8601) (44)
• Numbers & math (58)
• Vectors & matrices (27)
• Units & sizes (11)
• Graphs & scheduling (20)
• File paths (lexical) (20)
• Forms (6)
• Encoding & checksums (8)
• URLs & IP addresses (35)
• Versions & config (7)

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 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 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 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 transpose csv-transpose: Transpose a CSV matrix including the header row, then re-validate headers.

YAML, TOML, INI, XML & TSV

Convert YAML, TOML, INI, XML and TSV documents to and from JSON, with explicit rejections.

• INI to JSON ini-to-json: Convert an INI string to a JSON object.
• 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.
• TOML to JSON toml-to-json: Convert a TOML string to a JSON object.
• TSV to JSON tsv-to-json: Convert a complete TSV document into an array of string-valued objects.
• XML to JSON xml-to-json: Convert an XML string to a JSON object.
• YAML to JSON yaml-to-json: Convert a YAML string to a JSON object or array.

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 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 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 unique json-array-unique: Deduplicate a JSON array by structural equality, keeping first-seen order.
• 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 flatten json-flatten: Flatten a JSON value into a null-prototype map keyed by RFC 6901 JSON Pointers.
• 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 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 schema validate json-schema-validate: Validate a JSON instance against ComputeFirst Schema 1.0.
• 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.

• 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 diff stats text-diff-stats: Summarize a line-record diff as keep, insert, delete, and hunk counts.
• 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 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 NFC text-nfc: Normalize Unicode text to NFC (canonical composition).
• Text NFD text-nfd: Normalize Unicode text to NFD (canonical decomposition).
• 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 replace exact text-replace-exact: Replace exact UTF-16 substrings without regex, case folding, or Unicode normalization.
• Text slice codepoints text-slice-codepoints: Slice a string by Unicode code-point indexes, not UTF-16 code units.
• 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 word diff text-word-diff: Diff two texts as whitespace versus non-whitespace word tokens.

Sequences & diffs

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

• 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 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 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 and bucket ISO 8601 dates and UTC timestamps.

• Duration add duration-add: Sum mixed SI duration terms in nanoseconds and return the exact rational in a target unit.
• 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.
• 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 week to date iso-week-to-date: Convert an ISO-8601 week date to a YYYY-MM-DD calendar date.

Numbers & math

Exact integer, decimal and rational arithmetic, statistics and intervals.

• 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.
• 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.
• 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.
• 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.
• 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 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.

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 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 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, masses, temperatures and byte sizes.

• 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.
• 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.
• 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.

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 check form-response-check: Report missing required answers, nulls, type failures, and choice failures.
• Form response diff form-response-diff: Reconcile two form response sets by exact respondent id.

Encoding & checksums

Base64, UTF-8, hex bytes and non-cryptographic checksums.

• Adler-32 adler32: Adler-32 of UTF-8 bytes (RFC 1950). Integrity check only; no security claim.
• Base64 UTF-8 base64-utf8: Decode standard Base64 to UTF-8 text. Transformation only; no security claim.
• CRC-32 crc32: CRC-32 of UTF-8 bytes (ISO 3309 / ZIP / PNG polynomial). Integrity check only; no security claim.
• 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.
• 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.

• 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 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).

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.