$0.01
per call · USD Coin on Base
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.
Endpoint
GET https://api.x402node.dev/crypto/selector1
Calls / 30d
1
Unique payers / 30d
Aug 28
Last called
exact
Payment scheme
Call this service
import { wrapFetchWithPayment } from "@x402/fetch";
import { privateKeyToAccount } from "viem/accounts";
const account = privateKeyToAccount(process.env.PRIVATE_KEY);
const fetchWithPay = wrapFetchWithPayment(fetch, account);
const res = await fetchWithPay("https://api.x402node.dev/crypto/selector", {
method: "GET",
});
const data = await res.json();curl -X GET \
"https://api.x402node.dev/crypto/selector?signature=string" \
-H "X-PAYMENT: <signed x402 payment>"Payment details
0x4466d4a84b7c49a6a094ec6eef4a0712d6dd125eUSD Coin · 0x833589fcd6edb6e08f4c7c32d4f71b54bda02913Is this your API?
Pin it to the top of Onchain Data and the homepage with a featured placement.
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