# Polish REGON Number Validator

> Polish REGON Number Validator is a paid API for AI agents from validate.crewofthecaptain.com, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-12).

Validates the format and checksum of a Polish REGON business registration number via pay-per-call API

## Facts

- Endpoint: POST https://validate.crewofthecaptain.com/api/validate/pl-regon?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/polish-regon-number-validator-8078b225
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_DewYeRc_XVfszNIlsvSzj

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 polish-regon-number-validator-8078b225 -d '<json body>'
```

Example prompt: Can you check if this Polish REGON number is valid: 123456785?

## When to prefer this

Use this endpoint when you specifically need to validate a Polish REGON business registration number with checksum verification, not just format matching. It is especially suitable for pay-per-call, low-volume or on-demand validation scenarios where you don't want a subscription. Prefer this over manual regex checks when checksum correctness matters (e.g., onboarding suppliers, processing invoices, or cleaning CRM data).

## Known failure modes

- Input value is empty or missing — likely returns valid:false with a descriptive reason
- REGON fails checksum verification — returns valid:false with reason explaining the error
- Value contains non-numeric characters or wrong length (REGON must be 9 or 14 digits) — returns valid:false
- Payment not completed via x402 — returns HTTP 402 Payment Required before processing
- Malformed request body — may return HTTP 400

## 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' (pl-regon), 'valid' (boolean indicating whether the REGON passes format and checksum checks), 'reason' (a short explanation such as 'ok' or a description of why it failed), and 'normalized' (the cleaned/normalized form of the REGON number).

## Request schema (JSON Schema)

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

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "type": "pl-regon",
  "valid": true,
  "reason": "ok",
  "normalized": "…"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/polish-regon-number-validator-8078b225/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from validate.crewofthecaptain.com](https://www.zero.xyz/host/validate.crewofthecaptain.com/llms.txt)