Utilities

HMAC signature API

Compute an HMAC (sha1/sha256/sha512) of a message with a shared secret key, in hex or base64. Answers 'HMAC sign this', 'compute the webhook signature', 'sign this payload'.

Price$0.01per request

MethodPOST

Route/v1/util/hmac

StatusLive

MIME typeapplication/json

Rate limit120/minute

CacheNo cache

utilhmacsignaturewebhookcryptosignhash

API URLhttps://x402.hexl.dev/v1/util/hmac

Integration docs

Example request

{
  "message": "hello",
  "key": "secret",
  "algorithm": "sha256"
}

Example response

{
  "algorithm": "sha256",
  "encoding": "hex",
  "hmac": "88aab3ede8d3adf94d26ab90d3bafd4a2083070c3bcce9c014ee04a443847c0b"
}

Input schema

{
  "type": "object",
  "required": [
    "message",
    "key"
  ],
  "properties": {
    "message": {
      "type": "string"
    },
    "key": {
      "type": "string"
    },
    "algorithm": {
      "type": "string",
      "enum": [
        "sha1",
        "sha256",
        "sha512"
      ],
      "default": "sha256"
    },
    "encoding": {
      "type": "string",
      "enum": [
        "hex",
        "base64"
      ],
      "default": "hex"
    }
  }
}

Output schema

{
  "type": "object",
  "required": [
    "algorithm",
    "encoding",
    "hmac"
  ],
  "properties": {
    "algorithm": {
      "type": "string"
    },
    "encoding": {
      "type": "string"
    },
    "hmac": {
      "type": "string"
    }
  }
}