CSS minifier

CSS minifier: what this tool checks

CSS minifier converts pasted stylesheet source into a more compact form and shows the resulting CSS. Its character comparison gives developers a simple way to inspect the reduction before using the output. It is useful when preparing a standalone stylesheet or reviewing a small set of rules outside a larger build process.

How to use it

1. Save the original stylesheet and paste the CSS you want to process.
2. Submit the form and examine the output and character counts.
3. Copy the result for testing, then check the affected components at the screen sizes and states your stylesheet supports.

Understanding your results

The tool parses and minifies the supplied CSS; it does not inspect a website to determine which selectors are unused. A lower character count is not a measured improvement in layout performance, and it does not establish that all browser-specific or newly introduced syntax has been preserved correctly.

Frequently asked questions

Will it remove rules my website never uses?

Do not assume so. Determining whether a selector is unused requires knowledge of templates, dynamic classes, interactions, and responsive states that a pasted stylesheet alone does not provide.

What should I check before publishing the output?

Compare key layouts, hover and focus states, forms, animations, and narrow-screen behavior. Keep the readable source as your maintenance copy rather than relying only on the compact version.

Continue your review

Compact document markup using the HTML minifier, review element-level declarations with the Inline CSS checker, and inspect stylesheet reference totals through the HTTP requests checker.