# FastX402 Postal Code Validator

> FastX402 Postal Code Validator is a paid API for AI agents from fastx402.tools, paid per call via x402, $0.001/call, status down (last checked 2026-10-24).

Validates a postal code for a given country and returns whether it is valid, its normalized form, and the expected format.

## Facts

- Endpoint: GET https://fastx402.tools/postal-code-validate?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: down
- Last checked: 2026-10-24
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fastx402-postal-code-validator-971605d6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_3BHmQgnijkiyhoy4ycVA5

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 fastx402-postal-code-validator-971605d6
```

Example prompt: Can you check if '10001' is a valid postal code for the US and tell me its normalized format?

## When to prefer this

Use this endpoint when you need a lightweight, pay-per-call postal code validation without setting up an account or API key. Ideal for agents that occasionally need to verify shipping addresses or user-entered postal codes across multiple countries at minimal cost ($0.001 per call).

## Known failure modes

- Invalid or unsupported country code returns a validation failure or error
- Postal code with incorrect characters for the country returns valid:false
- Missing required query parameters (code or country) result in a 400-level error
- Payment failure via x402 protocol blocks the request before processing

## How this service works

216 pay-per-call tools for AI agents, from $0.001 per request in USDC on Base or Solana with x402. No account, no API key.

## Output

Returns a JSON object with the submitted postal code, a boolean indicating whether it is valid, the normalized version of the postal code, the expected format pattern for that country, and the country code.

## 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": [
      "country",
      "code"
     ],
     "properties": {
      "code": {
       "type": "string",
       "description": "Postal code to validate"
      },
      "country": {
       "type": "string",
       "description": "ISO 3166-1 alpha-2 country code (e.g. US, GB, CA, DE)"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "code": {
       "type": "string"
      },
      "valid": {
       "type": "boolean"
      },
      "format": {
       "type": "string"
      },
      "country": {
       "type": "string"
      },
      "normalized": {
       "type": "string"
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "code": "12345-6789",
  "valid": true,
  "format": "##### or #####-####",
  "country": "US",
  "normalized": "12345-6789"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fastx402-postal-code-validator-971605d6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from fastx402.tools](https://www.zero.xyz/host/fastx402.tools/llms.txt)