Encode function calldata API

Build EVM transaction calldata from a function signature and arguments (the inverse of decode-calldata). Answers 'encode a transfer call', 'build the calldata for this function', 'ABI-encode these args'.

Price$0.01per request

MethodPOST

Route/v1/evm/abi-encode

StatusLive

MIME typeapplication/json

Rate limit120/minute

CacheNo cache

evmabiencodecalldatatransactionfunction

API URLhttps://x402.hexl.dev/v1/evm/abi-encode

Integration docs

Example request

{
  "signature": "transfer(address,uint256)",
  "args": [
    "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
    "1000000000000000000"
  ]
}

Example response

{
  "signature": "transfer(address,uint256)",
  "functionName": "transfer",
  "calldata": "0xa9059cbb..."
}

Input schema

{
  "type": "object",
  "required": [
    "signature",
    "args"
  ],
  "properties": {
    "signature": {
      "type": "string",
      "examples": [
        "transfer(address,uint256)"
      ]
    },
    "args": {
      "type": "array"
    }
  }
}

Output schema

{
  "type": "object",
  "required": [
    "signature",
    "functionName",
    "calldata"
  ],
  "properties": {
    "signature": {
      "type": "string"
    },
    "functionName": {
      "type": "string"
    },
    "calldata": {
      "type": "string"
    }
  }
}