JavaScript Days-Hours-Minutes-Seconds Counter - Praveen Lobo /********************************************************************************************** * Days-Hours-Minutes-Seconds Counter script by Praveen Lobo * (http://PraveenLobo.com/techblog/javascript-counter-count-days-hours-minutes-seconds/) * This notice MUST stay intact(in both JS file and SCRIPT tag) for legal use. * http://praveenlobo.com/blog/disclaimer/ **********************************************************************************************/ function DaysHMSCounter(initDate, id){     this.counterDate = new Date(initDate);     this.container = document.getElementById(id);     this.update(); }   DaysHMSCounter.prototype.calculateUnit=function(secDiff, unitSeconds){     var tmp = Math.abs((tmp = secDiff/unitSeconds)) < 1? 0 : tmp;     return Math.abs(tmp < 0 ? Math.ceil(tmp) : Math.floor(tmp)); }   DaysHMSCounter.prototype.calculate=function(){     var secDiff = Math.abs(Math.round(((new Date()) - this.counterDate)/1000));     this.days = this.calculateUnit(secDiff,86400);     this.hours = this.calculateUnit((secDiff-(this.days*86400)),3600);     this.mins = this.calculateUnit((secDiff-(this.days*86400)-(this.hours*3600)),60);     this.secs = this.calculateUnit((secDiff-(this.days*86400)-(this.hours*3600)-(this.mins*60)),1); }   DaysHMSCounter.prototype.update=function(){     this.calculate();     this.container.innerHTML =         " " + this.days + " " + (this.days == 1? "day" : "days") +         " " + this.hours + " " + (this.hours == 1? "hour" : "hours") +         " " + this.mins + " " + (this.mins == 1? "min" : "mins") +         " " + this.secs + " " + (this.secs == 1? "sec" : "secs");     var self = this;     setTimeout(function(){self.update();}, (1000)); }   window.onload=function(){ new DaysHMSCounter('April 12, 2012 00:00:00', 'counter'); }   Contents of this DIV will be replaced by the timer