All tools on CSSTidy
Everything on this site runs 100% in your browser. No uploads, no accounts, nothing sent anywhere.
CSSTidy (main tool)
Client-side CSS formatter, beautifier, and minifier. Clean and compress stylesheets in your browser.
CSS Specificity Calculator
Paste selectors or a whole stylesheet and get the (ids, classes, types) specificity of each one, ranked by which rule wins the cascade. Handles :is(), :not(), :where() and :nth-child(of). Runs in your browser.
PX to REM Converter
Convert every px value in a stylesheet to rem (or rem back to px) with your own base font size. Leaves comments, strings, url() and media-query breakpoints alone. Runs in your browser.
Looking for explanations rather than a tool? CSSTidy guides cover 21 worked examples and gotchas.
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