# Bitcoin Address Balance Lookup via Blockstream

> Bitcoin Address Balance Lookup via Blockstream is a paid API for AI agents from api.x402node.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Returns confirmed/unconfirmed satoshi and BTC balances plus transaction count for a given Bitcoin address using Blockstream.info

## Facts

- Endpoint: GET https://api.x402node.dev/chain/btc-balance
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-x402node-dev-76cd3b38
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_YP--xRvZrRh60_HYZbV9Y

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 api-x402node-dev-76cd3b38
```

Example prompt: What's the current confirmed BTC balance and transaction count for the Bitcoin address bc1qxy2kgdygjrsqtzq2n0yrf2493p83kkfjhx0wlh — show me both in sats and BTC?

## When to prefer this

Use this endpoint when you need a quick, no-API-key lookup of a Bitcoin address balance on mainnet, including both confirmed and unconfirmed UTXOs and tx count. Prefer this over self-hosted node queries when you don't have infrastructure, and over Etherscan-style services for BTC-specific lookups. Ideal for AI agents monitoring BTC treasuries or wallet activity.

## Known failure modes

- Invalid Bitcoin address format returns an error
- Address not found on blockchain returns zero balances
- Blockstream.info upstream outage causes timeout or 5xx error
- Missing address parameter returns a bad request error
- Mainnet-only — testnet addresses will not return valid data

## How this service works

Bitcoin address balance and stats via blockstream.info (no key). Returns confirmed/unconfirmed sats and BTC, tx count. Use ?address=bc1... or 1.../3.... Built for AI agents tracking BTC wallets and treasury balances. Accepts payment on Base or Solana — either network works.

## Output

Returns an object with confirmed balance in satoshis, unconfirmed balance in satoshis, confirmed BTC balance, unconfirmed BTC balance, and total transaction count for the queried Bitcoin address.

## 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",
     "properties": {
      "address": {
       "type": "string",
       "description": "EVM/chain address (optional)"
      }
     }
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-x402node-dev-76cd3b38/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.x402node.dev](https://www.zero.xyz/host/api.x402node.dev/llms.txt)