Spring Sale! Save 30% on all books w/ code: PLANET24
Web Dev + WordPress + Security

New and Improved JavaScript Clock

Earlier this year, I posted an article explaining how to implement an unobtrusive JavaScript dynamic clock. While not completely earth-shattering or cutting-edge or anything like that, the dynamic JavaScript clock has received some great feedback from users who found the script to be exactly what they were looking for. In fact, a couple of weeks ago, Bill Brown went above and beyond by taking the time to improve the script with some great new features, including a “blinking seconds separator (for kicks)” and removal of “the need for the noscript tag.” Of course everything is yours to customize as desired. This quick post shares the complete script sent by Bill in a recent email (with slightly reformatted markup).

Demo

Unobtrusive JavaScript Clock

To build your own unobtrusive JavaScript clock, simply copy and paste the following code into a blank PHP document (no editing required!):

<!DOCTYPE>
<html>
	<head>
		<title>Demo: New and Improved JavaScript Clock - Perishable Press</title>
		<style type="text/css">
			.style {
				padding: 20px; font-family: monospace; font-weight: bold;
				border: 3px solid #c00; background-color: #f5f5e5;
				}
			.scripted .style {
				border: 3px double #ccc;
				}
		</style>
	</head>
	<body>
		
		<h1>New and Improved JavaScript Clock</h1>
		
		<div id="datetime" class="style">
			<span id="date"><?php echo date("l, F j, Y ~ "); ?></span> 
			<span id="time"><?php echo date("h:i:s A", time()); ?></span>
		</div>
		
		<script type="text/javascript">
			
			// Unobtrusive JavaScript Dynamic Clock
			// https://perishablepress.com/new-and-improved-javascript-clock/
			
			(function() { document.getElementsByTagName('html')[0].className='scripted' })();
			
			String.prototype.pad = function(l, s, t) {
				return s || (s = " "), (l -= this.length) > 0 ? 
				(s = new Array(Math.ceil(l / s.length) 
				+ 1).join(s)).substr(0, t = !t ? l : t == 1 ? 0 : Math.ceil(l / 2))
				+ this + s.substr(0, l - t) : this;
			};
			
			var addLoadEvent = function (func) {
				var oldonload = window.onload;
				if (typeof window.onload != 'function') {
					window.onload = func;
				} else {
					window.onload = function() {
						if (oldonload) {
							oldonload();
						}
						func();
					}
				}
			};
			
			var xClock = function () {
				var xC = null, xN = null, xH = null, xI = null,
				    xM = null, xS = null, xT = null, AP = null;
			
				if (!document.getElementById) return;
				xC = document.getElementById("time");
				if (!xC.nodeName) return;
				xN = new Date();
				xH = xN.getHours().toString().pad(2,'0',0);
				xM = xN.getMinutes().toString().pad(2,'0',0);
				xS = xN.getSeconds().toString().pad(2,'0',0);
				AP = (xH >= 12) ? "PM" : "AM";
				xH = (xH >= 13) ? (xH - 12) : xH;
				sS = (xN.getMilliseconds() >= 500) ? ":" : "·";
				xT = xH + ":" + xM + sS + xS + " " + AP;
				xC.innerHTML = xT;
				xI = !xI ? null : clearTimeout(xI);
				xI = setTimeout(xClock, 500);
			};
			
			addLoadEvent(xClock);
			
		</script>
		
	</body>
</html>

This new version has a number of useful improvements, like adding a scripted class to the <html> tag, 12-hour time format, and more. Thanks again to Bill Brown for sharing this new and improved JavaScript clock.

Download

Here you may download the source files for this tutorial/demo:

About the Author
Jeff Starr = Fullstack Developer. Book Author. Teacher. Human Being.
WP Themes In Depth: Build and sell awesome WordPress themes.

5 responses to “New and Improved JavaScript Clock”

  1. Hi.

    This is cool. So I can I replace the clock that comes with your Apathy theme with this clock? If that’s not possible, how do I add the “seconds” as you have on your site?

    Thank you!
    Chiwan

  2. Jeff Starr 2009/01/06 6:26 pm

    Hi Chiwan, I got your email and have sent some information that may help you with this.

  3. What about appending in the current timezone to the output (such as EST or EDT)?

  4. The blinking does not work well on Mac Firefox or Safari.

    Only the seconds have the bottom dot blinking (the top dot for seconds does not blink. The minutes does do not blink at all.

  5. Jeff Starr 2009/04/19 3:29 pm

    @Shefik: Sounds like a browser issue.. I am not sure how much control external JavaScript can provide over such minutia. Perhaps there is a way to resolve the issue with (X)HTML or CSS?

Comments are closed for this post. Something to add? Let me know.
Welcome
Perishable Press is operated by Jeff Starr, a professional web developer and book author with two decades of experience. Here you will find posts about web development, WordPress, security, and more »
BBQ Pro: The fastest firewall to protect your WordPress.
Thoughts
I live right next door to the absolute loudest car in town. And the owner loves to drive it.
8G Firewall now out of beta testing, ready for use on production sites.
It's all about that ad revenue baby.
Note to self: encrypting 500 GB of data on my iMac takes around 8 hours.
Getting back into things after a bit of a break. Currently 7° F outside. Chillz.
2024 is going to make 2020 look like a vacation. Prepare accordingly.
First snow of the year :)
Newsletter
Get news, updates, deals & tips via email.
Email kept private. Easy unsubscribe anytime.