Over time CSS files tend to end up with a lot of extra stuff that is no longer needed. When editing your CSS file, you may often abandon styles without even knowing it. Or you may want to make such a radical change that you are afraid of affecting other pages so you create a new style since you don't know if the style is used anywhere or not. After a couple of years, you can end up with a CSS file that is very bloated.

The CSS Redundancy Checker can help you find old styles that are no longer being used so that you can remove them from your CSS, thereby reducing your bandwidth usage and the latency experienced by your users. You just go to their site, enter the URL for the stylesheet and the URLs of your site. They then scan all of the pages you entered and they report to you on the styles that no longer are being used. You can then remove these unneeded entries from your CSS.