JSFiddle - React, Tailwind, and code Playground

by Dogbert

HTML

<div></div>

JavaScript

function Counter(o) {
  var startTime = +new Date;
  var interval = setInterval(() => {
    var now = o.start + ((+new Date) - startTime) / 1000 * o.speed;
    if (now > o.stop)
      now = o.stop
    o.el.innerText = Math.floor(now).toString().replace(/\B(?=(\d{3})+(?!\d))/g, ",");
    if (now === o.stop) {
      clearInterval(interval);
    }
  }, 30);
}

Counter({
  el: document.querySelector('div'),
  start: 2900000000,
  stop: 9000000000,
  speed: 523456789
});