bsn-validator

A tiny TypeScript/JavaScript package for validating Dutch BSN (Burgerservicenummer) numbers and generating fake BSNs for testing.

Install

npm

npm install bsn-validator

CDN

<script src="https://cdn.jsdelivr.net/npm/bsn-validator/dist/index.global.js"></script>

Quick Start

JavaScript

const { isValidBSN, generateFakeBSN } = require("bsn-validator");
const input = "123456782";
const fakeBSN = generateFakeBSN();

if (isValidBSN(input)) {
  console.log("Valid BSN");
}

console.log(fakeBSN);

TypeScript / ESM

import { isValidBSN, generateFakeBSN } from "bsn-validator";

const input = "123456782";
const fakeBSN = generateFakeBSN();

if (isValidBSN(input)) {
  console.log("Valid BSN");
}

console.log(fakeBSN);

CDN

<script src="https://cdn.jsdelivr.net/npm/bsn-validator/dist/index.global.js"></script>
<script>
  const input = "123456782";
  const fakeBSN = bsnValidator.generateFakeBSN();

  if (bsnValidator.isValidBSN(input)) {
    console.log("Valid BSN");
  }

  console.log(fakeBSN);
</script>

API

isValidBSN(bsn: string): boolean

Validates a BSN using the Dutch 11-check.

Rules:

• Accepts only 8 or 9 digits.
• Ignores leading/trailing spaces.
• Returns true when the number passes the 11-check, otherwise false.

generateFakeBSN(): string

Generates a fake BSN-like value intended for testing and development.

Notes:

• Generated values may coincide with a real BSN they are not guaranteed to be fictitious.
• The generated values are primarily intended for testing the application you are developing, not for real identity or production workflows.

Use Cases

• Form input validation for Dutch BSN fields.
• Backend request validation before processing.
• Creating mock BSN data for tests and demos.

References

• Check digit overview: https://en.wikipedia.org/wiki/Check_digit
• Citizen service number (BSN): https://www.government.nl/topics/personal-data/citizen-service-number-bsn

License

MIT