Speed up your site by compressing and caching your content with .htaccess

Please read Improving web site performance with Apache .htaccess for an updated version of this article.

.htaccess – gzip and cache your site for faster loading and bandwidth saving is one of the most popular posts on samaxes.
It’s basically on how to compress and cache your site content with Apache and .htaccess file.

It works like a charm, but it’s not yet the perfect configuration for me.
I wanted something that I can use out-of-the-box without having to rely on external extension modules or tools.

If you are lucky enough to have Apache 2 with your hosting provider you can use the mod_deflate module that comes bundled with it.

In order to compress your text files with this Apache’s module you just have to add the following lines to your .htaccess file:

<ifModule mod_deflate.c>
  <filesMatch ".(css|js|x?html?|php)$">
    SetOutputFilter DEFLATE

This will gzip all your .css, .js, .html, .html, .xhtml, and .php files.

A great .htaccess file example that will gzip your text files and cache all your static files, may look like:

# BEGIN Compress text files
<ifModule mod_deflate.c>
  <filesMatch ".(css|js|x?html?|php)$">
    SetOutputFilter DEFLATE
# END Compress text files

# BEGIN Expire headers
<ifModule mod_expires.c>
  ExpiresActive On
  ExpiresDefault "access plus 1 seconds"
  ExpiresByType image/x-icon "access plus 2592000 seconds"
  ExpiresByType image/jpeg "access plus 2592000 seconds"
  ExpiresByType image/png "access plus 2592000 seconds"
  ExpiresByType image/gif "access plus 2592000 seconds"
  ExpiresByType application/x-shockwave-flash "access plus 2592000 seconds"
  ExpiresByType text/css "access plus 604800 seconds"
  ExpiresByType text/javascript "access plus 216000 seconds"
  ExpiresByType application/javascript "access plus 216000 seconds"
  ExpiresByType application/x-javascript "access plus 216000 seconds"
  ExpiresByType text/html "access plus 600 seconds"
  ExpiresByType application/xhtml+xml "access plus 600 seconds"
# END Expire headers

# BEGIN Cache-Control Headers
<ifModule mod_headers.c>
  <filesMatch ".(ico|jpe?g|png|gif|swf)$">
    Header set Cache-Control "max-age=2592000, public"
  <filesMatch ".(css)$">
    Header set Cache-Control "max-age=604800, public"
  <filesMatch ".(js)$">
    Header set Cache-Control "max-age=216000, private"
  <filesMatch ".(x?html?|php)$">
    Header set Cache-Control "max-age=600, private, must-revalidate"
# END Cache-Control Headers

# BEGIN Turn ETags Off
<ifModule mod_headers.c>
  Header unset ETag
FileETag None
# END Turn ETags Off

# BEGIN Remove Last-Modified Header
<ifModule mod_headers.c>
  Header unset Last-Modified
# END Remove Last-Modified Header

This will surely improve your site performance by one order of magnitude. Try it!

Published by

Samuel Santos

Java developer, Open Source hacker, Web technologist, JUG Leader.

54 thoughts on “Speed up your site by compressing and caching your content with .htaccess”

  1. This is an excellent tip for your users, honest.
    It can speed up a WordPress installation by 50% without any caching plugin.

    Excellent post

  2. Using your 5-row mod_deflate snippet to pack my files, but unfortunately php files aren’t packed.

    What could the problem be?

  3. Apache is v2. JS, CSS and HTML files are compressed (only compressing PHP doesn’t work), so I guess it’s enabled.

    PHP files have .php extensions.

  4. Samuel -THANK YOU. I am pursuing an entirely different strategy for speeding services and this seems to fit quite nicely within that paradigm without sacrificing dynamic content.

  5. Thank you for your wonderful article. I implemented this in my site and the downloading speed has increased greatly. YSlow grade has improved from C to B. Some more things need to be done to get a grade of A!

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  7. Are you using this on your site? I’ve added this to my blogs, but ySlow firefox addon doesn’t seem to say that the expire headers are set, these are for both my blogs as well as your site

    1. I’m using a script very similar to this one except for mod_deflate module.
      Unfortunately my hosting provider is still using Apache 1.3.x; only Apache 2 or greater comes bundled with it.

  8. Just wanted to say thanks for this post, I added this to my .htaccess file and knocked off 2+ seconds on my page load times, and bumped up a letter grade in YSlow! I’m putting it on all my sites.

  9. Hi Santos

    Just wanna drop by to say Hello and Thanks.
    I used the second htaccess code above and everything went perfect.

    I’m amazed by the instant faster pageload time of my WP site.
    Thanks again for this valuable post.

    BTW, what is Etag ? and why do we unset it ?

    1. Entity tags (ETags) are a mechanism to check for a newer version of a cached file.
      By removing the ETag header, you disable caches and browsers from being able to validate files, so they are forced to rely on your Cache-Control and Expires header.

  10. This is a great resource. I have linked to it in a post I wrote about my meddlings, er optimizations, in WordPress at http://icanhazdot.net/2010/03/23/some-wordpress-stuff/.

    I added the following about your code to bypass the compression process for files that already have compressed versions that could be sent with a simple rewrite.

    RewriteEngine on
    #Check to see if browser can accept gzip files. If so and we have it - serve it!
    ReWriteCond %{HTTP:accept-encoding} gzip
    RewriteCond %{HTTP_USER_AGENT} !Safari
    #make sure there's no trailing .gz on the url
    ReWriteCond %{REQUEST_FILENAME} !^.+.gz$
    #check to see if a .gz version of the file exists.
    RewriteCond %{REQUEST_FILENAME}.gz -f
    #All conditions met so add .gz to URL filename (invisibly)
    RewriteRule ^(.+) $1.gz [QSA,L]

    Thanks for the post – it helped me out a lot.

  11. Heej Santos, Thanks for the great tips. It greatly improves the pageload speed. Just have one question, I’m getting this from Google PageSpeed: “Specify a cache validator”:

    The following resources are missing a cache validator. Resources that do not specify a cache validator cannot be refreshed efficiently. Specify a Last-Modified or ETag header to enable cache validation for the following resources.

    I know it’s turned off in your snippet, is there anyway to fix this error?

    1. Hi Ben,

      As you may find in a previous post – .htaccess – gzip and cache your site for faster loading and bandwidth saving, removing Last-Modified and ETag headers can indeed reduce your HTTP requests and improve your pages speed.

      However I’m not familiar with Google PageSpeed and I’m still using YSlow.
      You may try to comment the line Header unset Last-Modified to get a better score on Google tool and do some testing to check if you notice any degradation at all on your pages speed.

  12. Thanks for this.
    I have been messing/reading/testing/ around all day on optimizing a site and your article has helped me more than all the rest combined…Cheers

  13. Great example, thanks! I have one question: as I understand, this htaccess file removes the ETag and Last Modified.
    Google here: http://code.google.com/speed/page-speed/docs/caching.html
    recommends that quote:
    “It is important to specify one of Expires or Cache-Control max-age, and one of Last-Modified or ETag, for all cacheable resources”
    Do you think it’s better to keep the ETag on?

  14. Thank you so much, This worked great on our company OS Commerce site. it had resolved allot of the issue we were facing due to gzip for js.

    Again Thanks for your help

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