- 3 min
How to validate BSN, PGN & OWN in the Netherlands with TypeScript/JavaScript

The BSN, PGN and OWN in the Netherlands can be validated with a 11 proef (elf proef). In this post I show you the JavaScript and TypeScript code.
In the Netherlands, we have a few identification numbers from the government. In this example, you can create a function to validate both of them based on the specification.
- BSN = Burgerservice nummer
- PGN = Burgerservice nummer in schools where the student doesn't have a BSN. The PGN is also called OWN.
How to use the code?
Define the function in your code and call it like this:
TypeScript example
// PGN/OWNelfProefValidation('114435231', ElfproefType.own) // returns true;elfProefValidation('34564366349', ElfproefType.own) // returns false;// BSNelfProefValidation('232262536', ElfproefType.bsn) // returns true;elfProefValidation('247594057', ElfproefType.bsn) // returns false;
JavaScript example
// PGN/OWNelfProefValidation('114435231', 'own'); // returns true;elfProefValidation('34564366349', 'own')); // returns false;// BSNelfProefValidation('232262536', 'bsn')); // returns true;elfProefValidation('247594057', 'bsn')); // returns false;
Code
JavaScript function
function elfProefValidation(value, type) { let returnValue = false if (!value || value?.length === 0) { return true } if (value === '00000000000' || value.length !== 9) { return false } const values = value.split('') const firstCharacter = parseInt(values[0], 10) const lastCharacter = parseInt(values[values.length - 1], 10) const [a, b, c, d, e, f, g, h, i] = values.map(char => parseInt(char, 10)) let result = 0 if (type === 'bsn') { result = 9 * a + 8 * b + 7 * c + 6 * d + 5 * e + 4 * f + 3 * g + 2 * h + -1 * i returnValue = result > 0 && result % 11 === 0 } else if (type === 'own') { result = 9 * a + 8 * b + 7 * c + 6 * d + 5 * e + 4 * f + 3 * g + 2 * h returnValue = result > 0 && firstCharacter === 1 && result % 11 === lastCharacter + 5 } else { returnValue = false } return returnValue}
TypeScript
export enum ElfproefType { bsn, own}function elfProefValidation(value: string, type: ElfproefType): boolean { let returnValue = false; if (!value || value?.length === 0) { return true; } if (value === '00000000000' || value.length !== 9) { return false; } const values = value.split(''); const firstCharacter = parseInt(values[0], 10); const lastCharacter = parseInt(values[values.length - 1], 10); const [a, b, c, d, e, f, g, h, i] = values.map((char: string) => parseInt(char, 10)); let result = 0; if (type === ElfproefType.bsn) { result = 9 * a + 8 * b + 7 * c + 6 * d + 5 * e + 4 * f + 3 * g + 2 * h + -1 * i; returnValue = result > 0 && result % 11 === 0; } else if (type === ElfproefType.own) { result = 9 * a + 8 * b + 7 * c + 6 * d + 5 * e + 4 * f + 3 * g + 2 * h; returnValue = result > 0 && firstCharacter === 1 && result % 11 === lastCharacter + 5; } else { returnValue = false; } return returnValue;}
Thanks!
After reading this post, I hope you learned something new or are inspired to create something new! š¤
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RayRay
Iām Ray, a Frontend Developer since 2009 living in the Netherlands. I write about Frontend Development, JavaScript, TypeScript, Angular, CSS, VueJS and a lot more related topics.
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