# ERC-20 Token Balance Lookup

> ERC-20 Token Balance Lookup is a paid API for AI agents from anibalb.duckdns.org, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-31).

Returns the ERC-20 token balance for a given wallet address on a specified contract, including symbol, decimals, and balance.

## Facts

- Endpoint: GET https://anibalb.duckdns.org/x402/erc20-balance?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/erc-20-token-balance-lookup-cd9cf4c6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_i9k9ygTAsnpoXMM3OUhfp

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-cd9cf4c6
```

Example prompt: What's the USDC balance of wallet address 0xAbC123... on the USDC contract 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48?

## When to prefer this

Choose this endpoint when you need a fast, keyless, pay-per-call onchain ERC-20 balance read without setting up an account or API key. Ideal for agents that need to check token holdings programmatically on demand, especially when working in a x402 micropayment context. Prefer this over full node queries when you want a simple REST interface to ERC-20 balances without managing RPC infrastructure.

## Known failure modes

- Invalid or malformed wallet address returns an error
- Unknown or non-ERC-20 contract address may return zero balance or an error
- Missing required 'address' query parameter returns a validation error
- Network or RPC errors from the underlying blockchain node
- Contract address with no deployed code returns an error
- Rate limiting or payment failure via x402 if USDC payment is insufficient

## How this service works

Public data and utility APIs paid per call in USDC on Base (x402). No accounts, no API keys. 174 routes: crypto/equity data, onchain reads, DNS/email/security intel, geo/weather, x402 payment diagnostics, dev utilities and more.

## Output

Returns a JSON object with the token symbol (e.g. 'USDC'), the wallet address queried, the token balance as a number, the ERC-20 contract address, and the number of decimals used by the token.

## 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",
      "HEAD",
      "DELETE"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "address"
     ],
     "properties": {
      "address": {
       "type": "string"
      },
      "contract": {
       "type": "string"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "symbol": "USDC",
  "address": "0x...",
  "balance": 100,
  "contract": "0x...",
  "decimals": 6
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/erc-20-token-balance-lookup-cd9cf4c6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from anibalb.duckdns.org](https://www.zero.xyz/host/anibalb.duckdns.org/llms.txt)