# Toll402 Belgian National Register Number (RRN) Validator

> Toll402 Belgian National Register Number (RRN) Validator is a paid API for AI agents from toll402.dev, paid per call via x402, $0.001/call, status unknown (last checked 2026-09-14).

Offline validates an 11-digit Belgian National Register Number (Rijksregisternummer / Numéro de registre national), verifying check digits and parsing birth date, gender, and sequence number.

## Facts

- Endpoint: POST https://toll402.dev/v1/t/rrn_be_validate
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/toll402-belgian-national-register-number-rrn-validator-425f039b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_NzE3IUI0h07tW0BFQYowp

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 toll402-belgian-national-register-number-rrn-validator-425f039b -d '<json body>'
```

Example prompt: Can you validate this Belgian national register number for me — 85073003328 — and tell me if it's valid, plus extract the birth date and gender from it?

## When to prefer this

Use this endpoint when you need to validate Belgian national register numbers specifically, especially when offline validation (no external lookup) is sufficient and you also need structured extraction of birth date, gender, and sequence number from the RRN. Prefer over generic regex checks because it correctly handles the modulo-97 check digit algorithm including the year-2000 offset.

## Known failure modes

- Invalid or malformed input (non-11-digit string after stripping formatting) returns a validation error
- Check digit mismatch returns invalid status
- Ambiguous century for birth year (pre-2000 vs post-2000) may cause incorrect parsing if offset not applied
- Non-numeric characters that cannot be stripped cause parse failure

## How this service works

Offline validator for a Belgian National Register Number (Rijksregisternummer / Numéro de registre national), format YYMMDDXXXCC. Verifies the two check digits equal 97 minus (first nine digits mod 97), applying the +2,000,000,000 offset for persons born in year 2000 or later, and parses birth date, gender and sequence number.

## Output

Returns whether the RRN's check digits are valid (97 minus first-nine-digits mod 97, with +2,000,000,000 offset for year 2000+ births), along with the parsed birth date, gender indicator, and sequence number extracted from the number.

## 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",
    "bodyType",
    "body"
   ],
   "properties": {
    "body": {
     "type": "object",
     "required": [
      "value"
     ],
     "properties": {
      "value": {
       "type": "string",
       "description": "11-digit Belgian National Register Number, with or without dashes/spaces"
      }
     }
    },
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "POST"
     ],
     "type": "string"
    },
    "bodyType": {
     "enum": [
      "json",
      "form-data",
      "text"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/toll402-belgian-national-register-number-rrn-validator-425f039b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from toll402.dev](https://www.zero.xyz/host/toll402.dev/llms.txt)