Input CSS
Output
Minified CSS will appear here…
What is CSS minification?
CSS minification removes all characters that are not necessary for the browser to parse the stylesheet correctly — whitespace, newlines, comments, and redundant semicolons. This reduces the file size, which decreases page load time and improves performance scores.
A typical CSS file can be reduced by 20-40% through minification alone. When combined with GZIP compression on the server, total transfer size can be reduced by 70-80%.
Frequently asked questions
Does minification change how CSS works?
No. Minification only removes characters that are invisible to the browser parser — whitespace, newlines, and comments. The CSS rules themselves are unchanged and will behave identically.
Should I use minified CSS in development?
No. Keep readable CSS in development for easier debugging. Minify for production deployment. Most build tools (webpack, Vite, Parcel) minify CSS automatically during production builds.
What is the difference between minify and compress?
Minification removes unnecessary characters from source code. Compression (gzip, brotli) encodes the file more efficiently for transfer. They are complementary — minify first, then let the server compress for maximum savings.
How much does minification reduce file size?
Typically 15-40% depending on how much whitespace and comments the original file contains. Well-formatted code with lots of comments saves more than already-compact code.
What gets removed
/* Comments */
Spaces, tabs, newlines
Last semicolons in blocks
Leading zeros (.5 not 0.5)
Redundant units on zero (0 not 0px)
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