Chrome开发工具有一个审计选项卡，可以显示未使用的CSS选择器。

运行审计，然后，在Web页面性能下，参见删除未使用的CSS规则

谷歌Chrome开发工具有(目前试验)功能称为CSS概述，它将允许您找到未使用的CSS规则。

要启用它，请遵循以下步骤:

打开DevTools (Mac上的Command+Option+I;Control+Shift+I在Windows上) 转到DevTool设置(Mac上的功能+F1;F1 (Windows) 点击打开实验部分 启用“CSS概述”选项

我刚刚找到了这个网站——http://unused-css.com/

看起来不错，但我需要彻底检查它的输出“干净”css上传到任何我的网站之前。

此外，与所有这些工具，我需要检查它没有剥离id和类没有风格，但用作JavaScript选择器。

以下内容来自http://unused-css.com/，感谢他们推荐其他解决方案:

Latish Sehgal has written a windows application to find and remove unused CSS classes. I haven't tested it but from the description, you have to provide the path of your html files and one CSS file. The program will then list the unused CSS selectors. From the screenshot, it looks like there is no way to export this list or download a new clean CSS file. It also looks like the service is limited to one CSS file. If you have multiple files you want to clean, you have to clean them one by one. Dust-Me Selectors is a Firefox extension (for v1.5 or later) that finds unused CSS selectors. It extracts all the selectors from all the stylesheets on the page you're viewing, then analyzes that page to see which of those selectors are not used. The data is then stored so that when testing subsequent pages, selectors can be crossed off the list as they're encountered. This tool is supposed to be able to spider a whole website but I unfortunately could make it work. Also, I don't believe you can configure and download the CSS file with the styles removed. Topstyle is a windows application including a bunch of tools to edit CSS. I haven't tested it much but it looks like it has the ability to removed unused CSS selectors. This software costs 80 USD. Liquidcity CSS cleaner is a php script that uses regular expressions to check the styles of one page. It will tell you the classes that aren't available in the HTML code. I haven't tested this solution. Deadweight is a CSS coverage tool. Given a set of stylesheets and a set of URLs, it determines which selectors are actually used and lists which can be "safely" deleted. This tool is a ruby module and will only work with rails website. The unused selectors have to be manually removed from the CSS file. Helium CSS is a javascript tool for discovering unused CSS across many pages on a web site. You first have to install the javascript file to the page you want to test. Then, you have to call a helium function to start the cleaning. UnusedCSS.com is web application with an easy to use interface. Type the url of a site and you will get a list of CSS selectors. For each selector, a number indicates how many times a selector is used. This service has a few limitations. The @import statement is not supported. You can't configure and download the new clean CSS file. CSSESS is a bookmarklet that helps you find unused CSS selectors on any site. This tool is pretty easy to use but it won't let you configure and download clean CSS files. It will only list unused CSS files.

Chrome开发工具有一个审计选项卡，可以显示未使用的CSS选择器。

运行审计，然后，在Web页面性能下，参见删除未使用的CSS规则