Home/ Questions/Q 285021
In Process

The Archive Base Latest Questions

Editorial Team
  • 0
Asked: 2026-05-12T05:30:32+00:00

Today I have checked performance statistics of my website using YSlow . I got

  • 0

Today I have checked performance statistics of my website using YSlow. I got a warning (or error may be) which is as below

Add Expires headers
There are 15 static components without a far-future expiration date.

    * (no expires) http://www.example.com/video/css/global.css
    * (no expires) http://www.example.com/video/js/global.js
    * (no expires) http://www.example.com/video/images/main-bg.png

What this means and how to achieve this in PHP and ASP.NET both. I am on shared hosting server, so please tell me some way to do this using code, because I’ll not able to make any modification at the server end.

If I’ll expire the header then is there any chance that if I’ll make changes in the CSS then user will not get them right away because css and other files are cached for a certain time limit (1 month, week). Is it?

Is there any disadvantages of using expire headers??

Share

Leave an answer

You must login to add an answer.

Need An Account,

1 Answer

  1. Editorial Team

    PHP

    $time = time() + 3 * 24 * 60 * 60; // 3 days
header('expires: ' . gmdate('D, d M Y H:i:s \G\M\T', $time);

    But I would recommend you the Apache module mod_expires [1]. You can then put something like this in an .htaccess file

    <FilesMatch "\.(jpg|gif|png|css|js)$">
    ExpiresActive on
    ExpiresDefault "access plus 3 days"
</FilesMatch>

    This will match all Images, CSS and JavaScript files and set an Expires header for 3 days

    [1] http://httpd.apache.org/docs/2.0/mod/mod_expires.html

    • 0