Improve website YSlow performance grade in a blink of an eye

Website performance is much talked topic these days but still surprisingly large number of webmasters neglect the impact of site loading time for their SEO, visitor experience and ultimately sales.

Here is a quick tip to improve your website performance score (as measured by YSlow). It takes literally less then 5 minutes to implement.

Add these lines to your .htaccess file:

<FilesMatch "\.(ico|jpg|jpeg|png|gif|js|css|swf)$">
<IfModule mod_expires.c>
 ExpiresActive on
 ExpiresDefault "access plus 30 days"
</IfModule>
Header unset ETag
FileETag None
</FilesMatch>
 
AddOutputFilterByType DEFLATE text/html text/plain text/xml text/css application/javascript application/x-javascript  application/rss+xml application/atom_xml text/javascript

What this does is adds far expires header (make sure mod_expires is loaded in your apache config if you have problems) to your static content (images, js, css), turns off ETag headers and compresses files sent to the browser (also saving your bandwidth bill).

This will improve your score by at least a full grade, if not more.

Of course, improving YSlow grade will be just a side effect - your site will feel much quicker for browsing.

Feel free to post your YSlow results in comments before and after applying this tip.

Resources:
Website Optimization guide (originally for WordPress sites)
Adding version to theme CSS file
Javascript to Footer plugin
Yslow
Using Site speed as search ranking factor

Suggested reading:

• Alternative to YSlow – Page Speed
• Organic Search Optimization Strategy for 2011
• How to effectively use SEO Doctor for diagnosing website problems