JSFiddle - React, Tailwind, and code Playground

by serio

JavaScript

var formatUSCurrency = function (amt) {
  var rev = function (str) {
    return str.split('').reverse().join('');
  }
  var amt_rev = rev(amt.toString());
  return '$' + rev(amt_rev.match(/.{1,3}/g).join(','));
}

console.log(formatUSCurrency(1234556));
console.log(formatUSCurrency(12312837128932));
console.log(formatUSCurrency(123455));