JSFiddle - React, Tailwind, and code Playground

by Bhaumik Mehta

HTML

<span id="countdown" class="timer"></span>
<script>
    var upgradeTime = 172801;
var seconds = upgradeTime;
function timer() {
    var days        = Math.floor(seconds/24/60/60);
    var hoursLeft   = Math.floor((seconds) - (days*86400));
    var hours       = Math.floor(hoursLeft/3600);
    var minutesLeft = Math.floor((hoursLeft) - (hours*3600));
    var minutes     = Math.floor(minutesLeft/60);
    var remainingSeconds = seconds % 60;
    if (remainingSeconds < 10) {
        remainingSeconds = "0" + remainingSeconds; 
    }
    document.getElementById('countdown').innerHTML = days + ":" + hours + ":" + minutes + ":" + remainingSeconds;
    if (seconds == 0) {
        clearInterval(countdownTimer);
        document.getElementById('countdown').innerHTML = "Completed";
    } else {
        seconds--;
    }
}
</script>

JavaScript

var countdownTimer = setInterval('timer()', 1000);