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ERC20 Allowance Checker
x402
ERC20 Allowance Checker is a paid API for AI agents from apexfaucet.xyz, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-27).
Looks up the current ERC20 token allowance granted by an owner address to a spender contract on Ethereum, Base, Arc, or BNB Chain
Price / call$0.001
Success—
StatusUnknown
How this service works
Free APEX on X1, and free USDC plus APEX on Arc, three times a day. No gas, no sign-up. Plus a swap, a screener, APEX City and token checks.
Output
Returns a JSON object with ok (boolean), paid (amount charged), and a data object containing: allowance (human-readable amount), raw (raw on-chain value), symbol (token ticker), block (block number), blockTime (ISO timestamp of the block), chain, owner, token, spender addresses, and unlimited (boolean flag indicating max uint256 approval).
Example use cases
Pre-transaction approval audit
“Before I call the swap, check how much USDC allowance my wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 has given to the Uniswap router 0x68b3465833fb72A70ecDF485E0e4C7bD8665Fc45 on Base — I need to know if I have to approve first.”
Unlimited approval risk scan
“Has wallet 0xAbCd1234567890AbCd1234567890AbCd12345678 granted unlimited spending approval for the token 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 to the contract 0xDEF0987654321DEF0987654321DEF098765432 on Ethereum? Tell me if the allowance is set to unlimited.”
DeFi position monitoring on Arc
“Check the current token allowance for owner 0x1111111111111111111111111111111111111111 on the Arc chain — the token is 0x2222222222222222222222222222222222222222 and the spender is 0x3333333333333333333333333333333333333333. What's the exact allowance and when was the block confirmed?”
Technical details
Endpoint
GEThttps://apexfaucet.xyz/api/x402/evm-allowance?utm_source=zero.xyzWhen to prefer
Use this endpoint when you need a quick, on-chain read of an ERC20 allowance across Ethereum, Base, Arc, or BNB Chain without running your own RPC node. It is ideal for pre-transaction checks, approval audits, and DeFi monitoring agents. At $0.001 per call it is cost-effective for single lookups; prefer a direct RPC call only if you already have an RPC node available and want to avoid per-call fees.
Side effects
- Invalid Ethereum address format for token, owner, or spender (must match 0x + 40 hex chars)
- Unsupported chain value (only ethereum, base, arc, bnb accepted)
- Token contract does not exist on the specified chain
- RPC node unavailability or timeout causing lookup failure
- Payment failure — insufficient USDC balance for the $0.001 per-call fee
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Output
Schema · Response
{
"type": "json",
"schema": {
"type": "object",
"properties": {
"ok": {
"type": "boolean"
},
"data": {
"type": "object"
},
"paid": {
"type": "number"
}
}
},
"example": {
"ok": true,
"data": {
"ok": true,
"raw": "0",
"block": 26184816,
"chain": "ethereum",
"owner": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
"token": "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48",
"symbol": "USDC",
"spender": "0x000000000022D473030F116dDEE9F6B43aC78BA3",
"allowance": "0",
"blockTime": "2026-10-13T16:38:35.000Z",
"unlimited": false
},
"paid": 0.001
}
}Tags
x402
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