javascript how to seperate big numbers with comma code example

Example 1: number with commas js

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

Example 2: add comma to number javascript

var n = 34523453.345
n.toLocaleString()
"34,523,453.345"