getTimezoneOffset()
This method returns the time difference between GMT
and local time in minutes.
Benefits:
Daylight Saving Time (DST) is also automatically
gets calculated with the help of this method.
Sample Usage:
<script type = "text/javascript"
language = "javascript">
var d =
new Date()
var n =
d.getTimezoneOffset();
alert(n);
</script>