Hash noncrypto compute

hash-noncrypto-compute · version 1.0.0 · Hashing & signatures · free, no key needed

Compute FNV-1/1a, MurmurHash3 or xxHash over encoded input bytes, with an optional seed for algorithms that take one.

Use when you need to: fnv1a hash of this string · murmurhash3 of this key · xxhash32 checksum.

Decide before calling

Read the versioned contract and the supported scope below. Reuse hash-noncrypto-compute@1.0.0 when your input, required output and limits match it. Choose another approach for an unsupported operation.

Explain the choice

"I can use hash-noncrypto-compute@1.0.0 for fnv1a hash of this string. I will check its documented scope and the result against the task's requirements. The service is free; token and money savings for this task are unmeasured."

Supported

• fnv1a hash of this string
• murmurhash3 of this key
• xxhash32 checksum
• compute a shard key hash
• non-cryptographic hash for a cache key
• xxh64 of this text
• גיבוב לא קריפטוגרפי לצורך שיוך למחיצה

Not supported

• cryptographic or collision-resistant hashing (see hash-digest-compute)
• xxh3-64/xxh3-128 (not in this version; use xxh32 or xxh64)

Behavior

• algorithm fixes the output width: fnv1-32/fnv1a-32/murmur3-32/xxh32 are 32-bit; fnv1-64/fnv1a-64/xxh64 are 64-bit; murmur3-128-x64 is 128-bit as two 64-bit lanes.
• fnv1-32/fnv1a-32 use offset basis 0x811c9dc5 and prime 0x01000193 with 32-bit unsigned wraparound; fnv1-64/fnv1a-64 use offset basis 0xcbf29ce484222325 and prime 0x100000001b3 with 64-bit unsigned wraparound. FNV-1 multiplies then XORs the byte in; FNV-1a XORs the byte in then multiplies.
• fnv1-32, fnv1a-32, fnv1-64 and fnv1a-64 take no seed (the offset basis is fixed): seed must be omitted or exactly "0".
• murmur3-32 and murmur3-128-x64 take a 32-bit unsigned seed (0..4294967295, per the reference uint32_t seed signature, even though murmur3-128-x64 output is 128 bits); xxh32 also takes a 32-bit unsigned seed; xxh64 takes a 64-bit unsigned seed (0..18446744073709551615).
• seed is a decimal string (not a JSON number, to avoid IEEE-754 precision loss for 64-bit seeds); canonical form has no leading zeros (except the literal "0") and no sign. Omitting seed means "0".
• hex for the 32-bit algorithms is 8 lowercase hex digits, big-endian, of the unsigned result; for the 64-bit algorithms it is 16 lowercase hex digits, big-endian. For murmur3-128-x64, hex is 32 lowercase hex digits: the 16 raw output bytes of the reference MurmurHash3_x64_128 implementation in their native layout -- the h1 lane as 8 little-endian bytes, then the h2 lane as 8 little-endian bytes -- not a single big-endian 128-bit integer; this matches Python's mmh3 package and other common bindings.
• decimal is the unsigned base-10 string of the same value as hex for every algorithm with width <= 64 bits. For murmur3-128-x64 (width 128), decimal is null: the output is a 16-byte string, not a single scalar integer.
• Disclaimer: format transform only; provides no confidentiality, integrity, or authenticity.

Input

• text (string, required): max length 262144
• input_encoding (one of "utf8", "hex", "base64", "base64url", optional): default "utf8"
• algorithm (one of "fnv1-32", "fnv1a-32", "fnv1-64", "fnv1a-64", "murmur3-32", "murmur3-128-x64", "xxh32", "xxh64", required)
• seed (string, optional): pattern ^(0|[1-9][0-9]{0,20})$; default "0"

Output

• algorithm (one of "fnv1-32", "fnv1a-32", "fnv1-64", "fnv1a-64", "murmur3-32", "murmur3-128-x64", "xxh32", "xxh64", required)
• seed (string, required): pattern ^(0|[1-9][0-9]{0,20})$
• hex (string, required): pattern ^[0-9a-f]+$
• decimal (string or null, required): pattern ^(0|[1-9][0-9]*)$

Limits

• max input bytes: 16384

Example

Request input:

{
  "text": "",
  "algorithm": "fnv1-32"
}

Response:

{
  "result": {
    "algorithm": "fnv1-32",
    "seed": "0",
    "hex": "811c9dc5",
    "decimal": "2166136261"
  }
}

How to call it

MCP

Connect https://computefirst.net/mcp (setup), then call execute with:

{
  "id": "hash-noncrypto-compute",
  "version": "1.0.0",
  "input": {
    "text": "",
    "algorithm": "fnv1-32"
  }
}

HTTP (no key)

curl -X POST https://computefirst.net/v1/tools/hash-noncrypto-compute/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"text":"","algorithm":"fnv1-32"}'

The machine-readable contract is at /v1/tools/hash-noncrypto-compute/versions/1.0.0.

CLI

node cli.mjs run hash-noncrypto-compute 1.0.0 --input input.json --base-url https://computefirst.net

Get the client at /clients/cli/.

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