eighteen-digit-salesforce-id

npm install --save eighteen-digit-salesforce-id

var get18DigitId = require('eighteen-digit-salesforce-id');
console.log(get18DigitId('00341000001sKYi'));  // logs '00341000001sKYiAAM'

Note - if you pass in a string that's already 18 characters, you just get that same string back.

Note - if you pass in a string that's neither 15 nor 18 characters long, it throws an error.