Hash EIP-712 typed data API

Compute the EIP-712 digest a wallet signs for typed structured data — used by permits, EIP-3009 transfers, and x402 payment authorizations. Pass domain/types/primaryType/message, get the 32-byte hash.

Price$0.01per request

MethodPOST

Route/v1/evm/eip712-hash

StatusLive

MIME typeapplication/json

Rate limit120/minute

CacheNo cache

evmeip712typed-datapermiteip3009x402hash

API URLhttps://x402.hexl.dev/v1/evm/eip712-hash

Integration docs

Example request

{
  "domain": {
    "name": "Ether Mail",
    "version": "1",
    "chainId": 1
  },
  "types": {
    "Mail": [
      {
        "name": "contents",
        "type": "string"
      }
    ]
  },
  "primaryType": "Mail",
  "message": {
    "contents": "Hello"
  }
}

Example response

{
  "hash": "0x..."
}

Input schema

{
  "type": "object",
  "required": [
    "domain",
    "types",
    "primaryType",
    "message"
  ],
  "properties": {
    "domain": {
      "type": "object",
      "additionalProperties": true
    },
    "types": {
      "type": "object",
      "additionalProperties": true
    },
    "primaryType": {
      "type": "string"
    },
    "message": {
      "type": "object",
      "additionalProperties": true
    }
  }
}

Output schema

{
  "type": "object",
  "required": [
    "hash"
  ],
  "properties": {
    "hash": {
      "type": "string"
    }
  }
}