Hash digest compute

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

Compute a message digest (SHA-2, SHA-3, BLAKE2/3, MD5, RIPEMD-160, Keccak-256) over encoded input bytes.

Use when you need to: sha256 of this text · compute md5 hash · sha3-256 digest.

Decide before calling

Read the versioned contract and the supported scope below. Reuse hash-digest-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-digest-compute@1.0.0 for sha256 of this text. 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

• sha256 of this text
• compute md5 hash
• sha3-256 digest
• blake3 hash of a string
• what is the sha512 of this
• hex digest of this file content
• keccak256 hash
• חשב גיבוב sha256

Not supported

• guessing the algorithm from a bare digest string (see hash-digest-verify to check a known digest instead)
• password hashing for secure storage (see pbkdf2-compute; a bare digest is not a password hash)
• streaming or incremental hashing across multiple calls

Behavior

• algorithm selects the digest function. keccak-256 uses the original Keccak sponge domain-separation byte 0x01 (not the NIST SHA-3 0x06 padding) over the same rate/capacity as sha3-256, and produces a different digest than sha3-256 for the same input.
• output_bytes is required for shake128 and shake256 (no fixed output length), optional for blake3 (default 32), and forbidden for every other algorithm, which has exactly one fixed digest length.
• collision_broken is true only for md5 and sha1 (both practically broken for collision resistance); it is informational only and does not affect the computed digest.
• input_bytes counts decoded bytes after input_encoding is applied, not the character length of text.
• hex is lowercase with no separators; base64 is RFC 4648 section 4 padded; base64url is RFC 4648 section 5 unpadded.
• input_encoding defaults to utf8; a lone UTF-16 surrogate in text under utf8 is invalid_input.

Input

• text (string, required): max length 262144
• input_encoding (one of "utf8", "hex", "base64", "base64url", optional): default "utf8"
• algorithm (one of "md5", "sha1", "ripemd160", "sha224", "sha256", "sha384", "sha512", "sha512-224", "sha512-256", "sha3-224", "sha3-256", "sha3-384", "sha3-512", "keccak-256", "shake128", "shake256", "blake2b-256", "blake2b-512", "blake2s-256", "blake3", required)
• output_bytes (integer, optional): min 1; max 1024

Output

• algorithm (one of "md5", "sha1", "ripemd160", "sha224", "sha256", "sha384", "sha512", "sha512-224", "sha512-256", "sha3-224", "sha3-256", "sha3-384", "sha3-512", "keccak-256", "shake128", "shake256", "blake2b-256", "blake2b-512", "blake2s-256", "blake3", required)
• input_bytes (integer, required): min 0
• output_bytes (integer, required): min 1
• hex (string, required): min length 2; pattern ^[0-9a-f]+$
• base64 (string, required): min length 1; pattern ^[A-Za-z0-9+/]+=*$
• base64url (string, required): min length 1; pattern ^[A-Za-z0-9_-]+$
• collision_broken (boolean, required)

Limits

• max input bytes: 65536
• max output bytes: 1024

Example

Request input:

{
  "text": "abc",
  "algorithm": "sha256"
}

Response:

{
  "result": {
    "algorithm": "sha256",
    "input_bytes": 3,
    "output_bytes": 32,
    "hex": "ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad",
    "base64": "ungWv48Bz+pBQUDeXa4iI7ADYaOWF3qctBD/YfIAFa0=",
    "base64url": "ungWv48Bz-pBQUDeXa4iI7ADYaOWF3qctBD_YfIAFa0",
    "collision_broken": false
  }
}

How to call it

MCP

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

{
  "id": "hash-digest-compute",
  "version": "1.0.0",
  "input": {
    "text": "abc",
    "algorithm": "sha256"
  }
}

HTTP (no key)

curl -X POST https://computefirst.net/v1/tools/hash-digest-compute/versions/1.0.0/execute \
  -H "Content-Type: application/json" \
  -d '{"text":"abc","algorithm":"sha256"}'

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

CLI

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

Get the client at /clients/cli/.

Related tools

• Hash digest verify: Recompute a fixed-length digest over encoded input bytes and compare it to an expected digest given in any encoding.
• 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.
• 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.
• Ipfs cid compute: Compute the CIDv0, CIDv1 dag-pb and CIDv1 raw content identifiers 'ipfs add' would give a single-chunk file.
• Hash noncrypto compute: Compute FNV-1/1a, MurmurHash3 or xxHash over encoded input bytes, with an optional seed for algorithms that take one.
• Hmac compute: Compute HMAC-SHA256/SHA512/MD5/SHA-1/SHA-3/RIPEMD-160 (RFC 2104) over encoded key and message bytes.