api.onesource.io
x402Grade ALast checked 32 min ago
GET https://api.onesource.io/api/chain/erc20-balance
ERC20 token balance for any Ethereum wallet - USDC, USDT, DAI, or any token - via balanceOf (eth_call) on OneSource live Ethereum RPC
Price$0.003per chain read · paid in USD on Base
Uptime100%
5/5 probes · 337 ms
Score85Grade A
Paid usage, 30 days606payers · 612 calls
Warnings
Few repeat buyers Most payers called it only once, a pattern typical of crawlers or volume farming, so its usage counts half.
How to buy
This endpoint takes pay-per-call payments over x402. Call it once without paying to see its live price; any x402 client then pays and retries automatically.
curl -i -X GET "https://api.onesource.io/api/chain/erc20-balance"
# HTTP/1.1 402 Payment Required: price, asset and payTo are in the responseRecent checks
| Checked (UTC) | Result | Status | Time | Live price |
|---|---|---|---|---|
| 2026-10-11 12:16 | Valid 402 | 402 | 337 ms | $0.003 |
| 2026-10-11 07:46 | Valid 402 | 402 | 62 ms | $0.003 |
| 2026-10-11 03:16 | Valid 402 | 402 | 432 ms | $0.003 |
| 2026-10-10 23:00 | Valid 402 | 402 | 291 ms | $0.003 |
| 2026-10-10 17:15 | Valid 402 | 402 | 348 ms | $0.003 |
Receipts
No test purchases yet. Graded test purchases are next on our list; until then every number here comes from unpaid checks.
What a check proves