NFT owner lookup (ERC-721 · Erc721 Owner

by NFT owner lookup (ERC-721

GETBaseSolanaArbitrumPolygonMonadAvalancheeip155:1329OptimismFraxtaleip155:42220stellar:pubnetalgorand:wGHE2Pwdvd7S12BL5FaOP20EGYesN73ktiC1qzkkit8=

$0.002

per call · USD Coin on Base

Who owns this NFT? Calls ownerOf(tokenId) on any ERC-721 contract on Ethereum, Base, Polygon, Arbitrum, or Optimism. Complements nft-holdings (which lists a WALLET's NFTs) - this answers by TOKEN. Keyless multi-endpoint failover. ?contract=0x…&tokenId=123&network=ethereum

Endpoint

GET https://agent402.tools/api/erc721-owner

4

Calls / 30d

1

Unique payers / 30d

Aug 31

Last called

exact

Payment scheme

Call this service

TypeScript · @x402/fetch
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://agent402.tools/api/erc721-owner", {
  method: "GET",
});
const data = await res.json();
cURL
curl -X GET \
  "https://agent402.tools/api/erc721-owner?contract=0x57f1887a8BF19b14fC0dF6Fd9B2acc9Af147eA85&network=ethereum&tokenId=0xaf2caa1c2ca1d027f1ac823b529d0a67cd144264b2789fa2ea4d63a67c7103cc" \
  -H "X-PAYMENT: <signed x402 payment>"

Example response

{
  "contract": "0x57f1…",
  "network": "ethereum",
  "owner": "0x…",
  "tokenId": "0xaf2c…"
}

Payment details

Pay to0xabf4fabd7c416fb67202e5f9002389fc75e2a9d0
AssetUSD Coin · 0x833589fcd6edb6e08f4c7c32d4f71b54bda02913
NetworksBase, Solana, Arbitrum, Polygon, Monad, Avalanche, eip155:1329, Optimism, Fraxtal, eip155:42220, stellar:pubnet, algorand:wGHE2Pwdvd7S12BL5FaOP20EGYesN73ktiC1qzkkit8=
Schemesexact, upto

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