$0.0001
per call · USD Coin on Base
ERC-20 token balance for any wallet — USDC, USDT, DAI, or any token contract — via balanceOf eth_call, with decimals applied. Ethereum or Base mainnet. Pay 0.003 USDC.
Endpoint
POST https://app.heinrichstech.com/v1/cdp/chain/erc20-balance4
Calls / 30d
3
Unique payers / 30d
Sep 8
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://app.heinrichstech.com/v1/cdp/chain/erc20-balance", {
method: "POST",
headers: { "Content-Type": "application/json" },
body: JSON.stringify({
"address": "0x… holder",
"chain": "ethereum | base",
"token": "0x… ERC-20 contract"
}),
});
const data = await res.json();curl -X POST \
"https://app.heinrichstech.com/v1/cdp/chain/erc20-balance" \
-H "Content-Type: application/json" \
-d '{"address":"0x… holder","chain":"ethereum | base","token":"0x… ERC-20 contract"}' \
-H "X-PAYMENT: <signed x402 payment>"Example response
{
"chain": "base",
"ok": true,
"op": "erc20-balance"
}Payment details
0xda2f35d283c42dd60b965322394bc658a5c1769fUSD Coin · 0x833589fcd6edb6e08f4c7c32d4f71b54bda02913Is this your API?
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