Clear cached JavaScript includes in Firefox

• The web developer toolbar add-on has an option to let you disable caching.
• Firebug also does this. It is in the menu of the Net panel and is called Disable Browser Cache.

To bypass cache for one time in Firefox:

• Click the reload button while holding the shift key.
• Ctrl+F5
• Ctrl+Shift+R or Cmd+Shift+R
• for other browsers

Some web hosting services do cache the page server-side. When bypassing cache, web browsers will send a header to tell the server that it should not respond with the cached data.

In Firefox you can install a plugin called Web Developer Toolbar which has a appcache clear command

I think there is no way to do it programmatically but you could give a hint to the browser using something like

<script type="text/javascript" src='js/my.js?x=<?php echo rand(0,100) ?>'></script>

A very popular technique is to use a querystring parameter. Could look like

<script src="http://www.somedomain.com/foobar.js?v=1></script>

If you change this line into v=2 a browser will reload the script if it was cached before.

Browsers have user-facing facilities to clear the cache. Usually it's a menu option somewhere. You can't force the cache to be cleared.

What you can do is arrange for your scripts to be loaded from URLs that vary according to version number (or whatever):

<script src='http://your.site.com/js/big_script.js?version=2'></script>

Now when you update the code, you update the pages that use it:

<script src='http://your.site.com/js/big_script.js?version=3'></script>

That's a different URL, and it won't be in the cache.