On Yahoo!’s Developer pages you can find the YSlow plug-in for the Firefox Web browser (the plug-in works in conjunction with Firebug, which you should probably already be using anyway). After installing YSlow (and Firebug, if you haven’t already), restart Firefox, then load your Web page in Firebox. Click on the YSlow icon in the lower-right corner of the browser window, and you’ll see:
- A “report card” for the page’s performance
- Listings of specific strengths and weaknesses of the page
In case you’re curious, when I tested my site’s home page, I got a ‘B’ (85), which is a decent start. To improve the performance, I need to add expiration headers, use a CDN, and add ETags. And, to be honest, I didn’t even know what these last two were!
Update: I’ve started fixing some of the issues addressed by YSlow. You can read about that process in this other post.