# ERC-20 Token Balance Lookup (Base/Ethereum)

> ERC-20 Token Balance Lookup (Base/Ethereum) is a paid API for AI agents from webthree.ccwu.cc:8443, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-22).

Looks up the ERC-20 token balance for a given wallet address on Base or Ethereum, returning human-readable and raw balance values.

## Facts

- Endpoint: GET https://webthree.ccwu.cc:8443/v1/chain/erc20-balance?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-22
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/erc-20-token-balance-lookup-base-ethereum-7d7278c4
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Y15MppE-68a2Urt4dsf2X

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability erc-20-token-balance-lookup-base-ethereum-7d7278c4
```

Example prompt: What's the USDC balance of wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 on Base — use the USDC contract 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913?

## When to prefer this

Use this endpoint when you need a quick, no-account-required ERC-20 token balance lookup on Base or Ethereum mainnet, paid per call via USDC over x402. Prefer it for lightweight agent workflows that need on-chain balance data without maintaining a Web3 node or API key subscription.

## Known failure modes

- Invalid or malformed EVM address returns an error
- Unsupported chain value (must be 'base' or 'ethereum') returns a validation error
- Invalid ERC-20 contract address (not a real token contract) may return zero or an error
- Network/RPC unavailability causes a timeout or 5xx response
- Missing required query parameters (chain, token, address) results in a 400 error

## How this service works

Pay-per-call website uptime/latency/TLS checks and fetch-to-Markdown, measured from Hub Europe (Germany). USDC on Base via x402. No account or API key.

## Output

Returns a JSON object with the wallet's token balance as a human-readable decimal string (e.g. '12.5'), the raw integer balance, the token symbol (e.g. 'USDC'), and the number of decimals used by the contract.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "chain",
      "token",
      "address"
     ],
     "properties": {
      "chain": {
       "type": "string",
       "example": "base",
       "description": "base or ethereum"
      },
      "token": {
       "type": "string",
       "example": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
       "description": "ERC-20 contract address"
      },
      "address": {
       "type": "string",
       "example": "0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045",
       "description": "0x EVM address"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "raw": "12500000",
  "symbol": "USDC",
  "balance": "12.5",
  "decimals": 6
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/erc-20-token-balance-lookup-base-ethereum-7d7278c4/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from webthree.ccwu.cc:8443](https://www.zero.xyz/host/webthree.ccwu.cc%3A8443/llms.txt)