That's easy to find with a quick
Google Search
EDIT: First result gave this:
code:
<script language="JavaScript">
<!--
// please keep these lines on when you copy the source
// made by: Nicolas - http://www.javascript-page.com
var clockID = 0;
function UpdateClock() {
if(clockID) {
clearTimeout(clockID);
clockID = 0;
}
var tDate = new Date();
document.theClock.theTime.value = ""
+ tDate.getHours() + ":"
+ tDate.getMinutes() + ":"
+ tDate.getSeconds();
clockID = setTimeout("UpdateClock()", 1000);
}
function StartClock() {
clockID = setTimeout("UpdateClock()", 500);
}
function KillClock() {
if(clockID) {
clearTimeout(clockID);
clockID = 0;
}
}
//-->
</script>
<body onload="StartClock()" onunload="KillClock()">
<center><form name="theClock">
<input type=text name="theTime" size=8>
<form></center>