function Counter(ms,accuracy){
    var duration = ms;
    var progress = 0;
    var accuracy = accuracy || 100; //100ms update default


    var interval = setInterval(tick(), accuracy);

    function tick(){
        progress += accuracy;
         console.log(progress);
        if (progress >= duration){
            window.clearInterval(interval);
            console.log("Timer finished");
        }

    }

}


var x = new Counter(20000);