Api Endpoint

api.x402node.dev

Compute the 4-byte function/error selector and full keccak topic from a solidity signature, e.g. transfer(address,uint256). For decoding tx input prefixes and matching event topics. function selector, 4byte, method id, event topic, keccak signature Accepts payment on Base or Solana — either network works.

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Offering

Provider: api.x402node.dev
Method: GET
Offering type: Api Endpoint
Transport type: http
Category: Blockchain And Crypto
Delivery: Not provided
Pricing model: Not provided
x402 version: 2

Endpoint context

URL: https://api.x402node.dev/crypto/selector
MIME type: application/json
First seen: 2026-10-16T01:58:48.885Z
Last seen: 2026-11-02T15:58:13.905Z
Tags: None supplied

Website

Payment pricing

x402 payment terms are the authoritative price for calling this endpoint.

Payment option 1: 0.01 USDC
Atomic price: 10000 · Network: eip155:8453 · Asset: USDC · Scheme: exact
Payment option 2: 0.01 USDC
Atomic price: 10000 · Network: solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp · Asset: USDC · Scheme: exact

Raw x402 terms

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "10000",
    "payTo": "0x4466d4A84b7c49a6A094ec6eef4a0712D6dd125e"
  },
  {
    "scheme": "exact",
    "network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
    "asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
    "amount": "10000",
    "payTo": "9urRvUx69HqAopg1JGV9P9wR7JdKoztzdkuNyJ8Eo1up"
  }
]

Observed health

Status: Healthy
Latest latency: 180 ms
Average latency: 372 ms
HTTP status: 402
Last checked: 2026-11-02T15:58:13.899Z
Reachability: 100% over 13 checks

Latency is measured to the first response headers. A reachable result does not verify response accuracy or merchant identity.

Input schema

{
  "type": "object",
  "properties": {
    "type": {
      "type": "string",
      "const": "http"
    },
    "method": {
      "type": "string",
      "enum": [
        "GET"
      ]
    },
    "queryParams": {
      "type": "object",
      "properties": {
        "signature": {
          "type": "string",
          "description": "canonical signature, e.g. transfer(address,uint256) (required)"
        }
      },
      "required": [
        "signature"
      ]
    }
  },
  "required": [
    "type",
    "method"
  ],
  "additionalProperties": false
}

Output schema

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "type": "object",
  "properties": {
    "input": {
      "type": "object",
      "properties": {
        "type": {
          "type": "string",
          "const": "http"
        },
        "method": {
          "type": "string",
          "enum": [
            "GET"
          ]
        },
        "queryParams": {
          "type": "object",
          "properties": {
            "signature": {
              "type": "string",
              "description": "canonical signature, e.g. transfer(address,uint256) (required)"
            }
          },
          "required": [
            "signature"
          ]
        }
      },
      "required": [
        "type",
        "method"
      ],
      "additionalProperties": false
    }
  },
  "required": [
    "input"
  ]
}