slow-luhn

Calculate or validate Luhn algorithm

Usage

const luhn = require('slow-luhn');
luhn('4564456445644564'); // true
luhn('4564456445644563'); // false
luhn('456445644564456', true); // 4

Method

Luhn(checkString, [getChecksumDigit = false]);
+ If getChecksumDigit is true, return (Number) checksum
+ Else return result Luhn test checkString