How to prevent caching of my Javascript file? [duplicate]

I have a simple html:

<html>
<body>
<head>
<meta charset="utf-8">
<meta http-equiv='cache-control' content='no-cache'>
<meta http-equiv='expires' content='0'>
<meta http-equiv='pragma' content='no-cache'>
<script src="test.js"></script>
</body>
</html>

In test.js I changed a Javascript function, but my browser is caching this file. How to disable cache for script src?


Add a random query string to the src

You could either do this manually by incrementing the querystring each time you make a change:

<script src="test.js?version=1"></script>

Or if you are using a server side language, you could automatically generate this:

ASP.NET:

<script src="test.js?rndstr=<%= getRandomStr() %>"></script>

More info on cache-busting can be found here:

https://curtistimson.co.uk/post/front-end-dev/what-is-cache-busting/


<script src="test.js?random=<?php echo uniqid(); ?>"></script>

EDIT: Or you could use the file modification time so that it's cached on the client.

<script src="test.js?random=<?php echo filemtime('test.js'); ?>"></script>

Configure your webserver to send caching control HTTP headers for the script.

Fake headers in the HTML documents:

  1. Aren't as well supported as real HTTP headers
  2. Apply to the HTML document, not to resources that it links to

You can append a queryString to your src and change it only when you will release an updated version:

<script src="test.js?v=1"></script>

In this way the browser will use the cached version until a new version will be specified (v=2, v=3...)


You can add a random (or datetime string) as query string to the url that points to your script. Like so:

<script type="text/javascript" src="test.js?q=123"></script> 

Every time you refresh the page you need to make sure the value of 'q' is changed.