CSS Minifier
CSS usually arrives formatted for humans — indented, spaced out and full of comments. That is fine in an editor, but it is extra weight on a live site. Paste that stylesheet into Fixpio’s CSS minifier and it comes back stripped down for production: comments removed, whitespace collapsed and the last semicolon in each rule dropped. It works entirely in your browser, and it shows you exactly how many bytes you saved before you ship it.
Minify CSS
Paste CSS below and get a compact version back, with the saving shown.
Paste some CSS and press Minify CSS to see the before-and-after sizes here.
What smaller CSS does for you
Minifying will not fix a stylesheet — but it decides how much of it a visitor has to download.
Faster first visits
The first time someone opens a page, the stylesheet has to arrive before the layout settles. Stripping comments and whitespace trims that download without touching a single rule.
One production copy
Stylesheets edited by several people drift into several styles. Running the result through the same minifier gives every release a single, predictable production copy.
Easy to check and share
The before-and-after sizes are shown on the page, so you can see the saving at a glance and paste the result straight into a build, a ticket or a deployment.
About this minifier
CSS rarely stays small on its own. A stylesheet grows rule by rule as a design evolves, picks up comments explaining why a hack was needed, and gets formatted for the next person who has to read it. A CSS minifier online is the step that turns that working file into a production file: paste the stylesheet in, and the comments disappear, the spacing collapses and the result is a compact version of the same rules — ready to serve to visitors who never needed the commentary in the first place.
Fixpio’s tool keeps that job deliberately small. It is a basic CSS minifier rather than a full optimiser: it will not merge rules, rename selectors or rewrite your declarations, and it says so on the page. What it offers instead is a quick CSS compress that happens entirely on your own machine, with the saving measured in bytes and shown before you copy anything out. For a stylesheet carrying a client’s design, that local processing is the feature — the file is shrunk where it sits and goes nowhere else.
Frequently asked questions
Honest answers about what minifying changes — and what it cannot do.
What does this tool actually do to CSS?
It removes comments, collapses whitespace, strips spaces around punctuation such as braces, colons and semicolons, and drops the last semicolon in each rule. Selectors, property names and values stay as you wrote them; only the unnecessary characters go.
How do I minify CSS on this page?
Paste your CSS into the “CSS input” box and press Minify CSS. The compact version appears in the “Minified CSS” box, with a stats line showing the original size, the minified size and the percentage saved. Copy the result into your site or build.
Will minifying change how my site looks?
It should not: the rules themselves are unchanged, so the rendered page should look the same. Minifying is a layout change to the file, not to the design. Test the minified stylesheet on a staging page first, and keep your original until you are satisfied.
Does it validate my CSS?
No. This is a basic minifier, not a validator or linter. It will happily minify CSS containing a typo, so check the original stylesheet in your editor or a validator if something looks wrong after minifying.
Is it safe to paste a client stylesheet here?
Your CSS is not sent anywhere: the minifying runs entirely in your web browser, on your own device, and nothing is uploaded or stored. When you close the tab, nothing of your stylesheet remains with us.
Is it free to use?
Yes. Minifying CSS costs nothing, and there is no account, sign-up or software installation involved. Open the page, paste your CSS, minify it and take the result with you.