JSFiddle - React, Tailwind, and code Playground

HTML

<head>
<script>
function startTime() {
    var today = new Date();
    var h = today.getHours();
    var m = today.getMinutes();
    var s = today.getSeconds();
    var ampm = h >= 12 ? 'PM' : 'AM';
  h = h % 12;
  h = h ? h : 12; // the hour '0' should be '12'
    m = checkTime(m);
    s = checkTime(s);
    document.getElementById('txt').innerHTML =
    h + ":" + m + ":" + s + " " + ampm;
    var t = setTimeout(startTime, 500);
}
function checkTime(i) {
    if (i < 10) {i = "0" + i};  // add zero in front of numbers < 10
    return i;
}
</script>
</head>


<body onload="startTime()">
<div id="txt"></div>