JSFiddle - React, Tailwind, and code Playground

by Zdeněk Bauer

HTML

<div id="odpocet" data-datum="2014-01-27 10:00"></div>

JavaScript

var cas = new Date($('#odpocet').data('datum'));
	var miliseconds = cas.getTime() - new Date().getTime() ;
	
	function countdown(){
    var days = Math.floor(miliseconds / 36e5 / 24),
        hours = Math.floor(miliseconds / 36e5 - (days*24)),
        mins = Math.floor((miliseconds % 36e5) / 6e4),
        secs = Math.floor((miliseconds % 6e4) / 1000);
        $('#odpocet').html(days+':'+hours+':'+mins+':'+secs);  
	}

	setInterval(function(){
		miliseconds -= 1000;
		countdown();
	}, 1000);