dropcss | An exceptionally fast , thorough and tiny unused-CSS cleaner

dropcss is a HTML library. dropcss has no bugs, it has no vulnerabilities, it has a Permissive License and it has medium support. You can download it from GitHub.

DropCSS takes your HTML and CSS as input and returns only the used CSS as output. Its custom HTML and CSS parsers are highly optimized for the 99% use case and thus avoid the overhead of handling malformed markup or stylesheets, so well-formed input is required. There is minimal handling for complex escaping rules, so there will always exist cases of valid input that cannot be processed by DropCSS; for these infrequent cases, please start a discussion. While the HTML spec allows html, head, body and tbody to be implied/omitted, DropCSS makes no such assumptions; selectors will only be retained for tags that can be parsed from provided markup. It's also a good idea to run your CSS through a structural optimizer like clean-css, csso, cssnano or crass to re-group selectors, merge redundant rules, etc. It probably makes sense to do this after DropCSS, which can leave redundant blocks, e.g. .foo, .bar { color: red; } .bar { width: 50%; } -> .bar { color: red; } .bar { width: 50%; } if .foo is absent from your markup. More on this project's backstory & discussions: v0.1.0 alpha: /r/javascript, Hacker News and v1.0.0 release: /r/javascript.