What is a CSS Minifier?
Minifying CSS removes everything a browser does not need: comments, indentation, the last semicolon in a block, and the space either side of a colon or brace.
Paste your stylesheet and get the minified version plus the byte saving. It runs in your browser, so nothing is uploaded.
This one is deliberately conservative. Strings and the contents of url() are protected so nothing inside them is rewritten, and a comment beginning with an exclamation mark survives, which is the convention licence headers rely on. A minifier that saves another two percent but breaks one stylesheet in fifty is not worth using.
Frequently asked questions
Is minified CSS safe to ship?
Yes. Minifying only removes characters the parser ignores. This tool additionally protects strings and url() contents, and preserves licence comments written as slash star exclamation mark.
How much smaller will it get?
Typically twenty to thirty percent on hand written CSS, and far less on output that a build tool has already processed. The tool shows the exact figure for your file.
Should I minify by hand or in the build?
In the build, always, so the readable source stays the thing you edit. This tool is for the times you have a stylesheet in front of you and no build to run it through.
Is my CSS uploaded?
No. It is processed in your browser and never transmitted.