JavaScript provides two different methods to manage timer on any web page.
1 setInteval(function(){},time);
2 clearInterval()
<!DOCTYPE html>
<html>
<head>
<title></title>
<script>
// Set the date we're counting down to
var countDownDate = new Date("OCT 5, 2019 20:18:00").getTime();
// Update the count down every 1 second
var x = setInterval(
function() {
// Get today's date and time
var now = new Date().getTime();
// Find the distance between now and the count down date
var distance = countDownDate - now;
// Time calculations for days, hours, minutes and seconds
var days = Math.floor(distance / (1000 * 60 * 60 * 24));
var hours = Math.floor((distance % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60));
var minutes = Math.floor((distance % (1000 * 60 * 60)) / (1000 * 60));
var seconds = Math.floor((distance % (1000 * 60)) / 1000);
// Display the result in the element with id="demo"
document.getElementById("demo").innerHTML = days + "d " + hours + "h "
+ minutes + "m " + seconds + "s ";
// If the count down is finished, write some text
if (distance < 0) {
clearInterval(x);
document.getElementById("demo").innerHTML = "EXPIRED";
}
}, 1000);
</script>
</head>
<body>
<div id="demo"></div>
</body>
</html>
Second Example of Timer Code to Create Slider prefer this link
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