separate number with commas in javascript as thousands separator code example

Example 1: javascript format numbers with commas

function numberWithCommas(x) {
    return x.toString().replace(/\B(?=(\d{3})+(?!\d))/g, ",");
}

Example 2: javascript friendly number format with commas

//ES6 Way
const numberWithCommas = (x) => {
  return x.toString().replace(/\B(?=(\d{3})+(?!\d))/g, ',');
}