# Base Blockchain Address Nonce Lookup

> Base Blockchain Address Nonce Lookup is a paid API for AI agents from heb-utils-x402.hebutils-api.workers.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-11).

Returns the current transaction nonce for a given Base blockchain address

## Facts

- Endpoint: GET https://heb-utils-x402.hebutils-api.workers.dev/base-nonce?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-11
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/base-blockchain-address-nonce-lookup-972c988a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_3i2IDQuDKdan3nRfC-QYx

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 base-blockchain-address-nonce-lookup-972c988a
```

Example prompt: What is the current nonce for the Base address 0xAbC123...? I need it before I send my next transaction.

## When to prefer this

Use this endpoint when you need the current on-chain nonce for a Base blockchain address, particularly before constructing or signing a transaction to avoid nonce collisions. Prefer this over generic RPC calls when you want a simple pay-per-call REST API without running your own Base node or managing RPC provider credentials.

## Known failure modes

- Missing or invalid address parameter returns an error or unexpected result
- Non-checksummed or malformed Ethereum address may fail
- Address with zero transactions returns nonce of 0, which may be confused with an error
- Network or worker downtime may cause 5xx errors
- Payment failure via x402 protocol results in 402 response before any data is returned

## How this service works

Pay-per-call utility APIs in USDC on Base: Hebrew calendar and text tools, Shabbat times, Base token control-risk screen and address summary, plus finance arithmetic tools. General information and arithmetic only; not investment, tax or legal advice and not a recommendation to buy, sell or hold anything.

## Output

Returns a JSON object containing a single integer field 'nonce' representing the current transaction count (nonce) for the queried Base address, indicating how many transactions the address has sent.

## 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"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "nonce": 0
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/base-blockchain-address-nonce-lookup-972c988a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from heb-utils-x402.hebutils-api.workers.dev](https://www.zero.xyz/host/heb-utils-x402.hebutils-api.workers.dev/llms.txt)