# IBAN Format & Checksum Validator (x402)

> IBAN Format & Checksum Validator (x402) is a paid API for AI agents from x402-test.crewofthecaptain.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-12).

Validates the format and checksum of an IBAN bank account number, returning a validity flag and normalized form, paid per-call via x402.

## Facts

- Endpoint: POST https://x402-test.crewofthecaptain.com/api/validate/iban?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/iban-format-checksum-validator-x402-5dd4cd9b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_iR5FO5aEAhejFJ2MgAfz_

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 iban-format-checksum-validator-x402-5dd4cd9b -d '<json body>'
```

Example prompt: Can you check if this IBAN is valid: DE89370400440532013000?

## When to prefer this

Use this endpoint when you need a lightweight, pay-per-call IBAN validation with no subscription — ideal for low-volume or sporadic checks where a recurring SaaS fee is wasteful. It is purpose-built for IBAN specifically (not a generic string validator), returns a normalized form, and costs only $0.001 per call via x402 micropayments.

## Known failure modes

- Invalid format returns valid:false with a descriptive reason string
- Empty or missing value field may return a 400 error
- Non-IBAN strings (e.g. email addresses) will fail validation with an appropriate reason
- Payment failure via x402 results in a 402 response if USDC balance is insufficient

## How this service works

Format and checksum validation for IBAN, EU VAT, Polish NIP/REGON/PESEL and email, pay-per-call via x402. Only $0.001 (0.1 cent) per check, paid via x402 in USDC on Base.

## Output

A JSON object containing: 'type' (always 'iban'), 'valid' (boolean), 'reason' (ok or an error message describing why it failed), and 'normalized' (the canonically formatted IBAN string).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "value": {
   "type": "string",
   "maxLength": 512
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "type": "iban",
  "valid": true,
  "reason": "ok",
  "normalized": "…"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/iban-format-checksum-validator-x402-5dd4cd9b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-test.crewofthecaptain.com](https://www.zero.xyz/host/x402-test.crewofthecaptain.com/llms.txt)