Fastest JavaScript implementation of the Luhn algorithm.

Benchmarks here.

This algorithm (also known as Luhn formula) is useful to validate a variety of identification numbers (e.g. credit card numbers).

~1KB.

UMD builds for development - index.js and index.js.map - and production - index.min.js - available.

So it's installable both on node and/or for browsers.

$ npm install luhn-alg
$ bower install luhn-alg

Simplest API ever.

luhn(x: number): boolean

Try it in node.

$ > var luhn = require('luhn-alg');
$ > luhn('4242424242424242');
$ true

Include the UMD build (e.g., index.min.js) and you'll have a luhn function on the window/global scope.

Or use CommonJS, AMD, WTFYW etc.

This project is fully unit tested on:

• node.js 0.10, node.js 0.12, io.js
• about 50 browser versions

• ShirtlessKirk's popular gist
• Anyone contributing and improving performances