What the CSS Minifier does
This is a live, two-pane minifier. Your original CSS sits on the left and the minified version appears on the right, updating the moment you type, with no button to press. As you go, each pane shows its own size and a summary line reads out your original size, the minified size and how much smaller the result is, so you can see the win at a glance. Under the hood it removes comments, collapses runs of whitespace and line breaks, deletes spaces around braces, colons, semicolons and commas, and drops unnecessary trailing semicolons. What you get back is the exact same styling in far fewer bytes. When you are happy, one click copies the output or downloads it as a .min.css file. It is handy for front-end developers, students learning CSS, and anyone shipping a site who wants a lighter file without setting up a build step.
How to use it
- Paste or type your CSS into the input pane on the left, or hit Load example to drop in a sample stylesheet.
- The minified CSS appears instantly in the right pane as you type, with each pane’s size and the percent saved shown above.
- Click Copy to grab the result, or Download to save it as a
.min.cssfile. - Use Clear to empty both panes and start fresh.
There are no settings to fiddle with, and nothing is uploaded. Paste, read the savings, copy or download, done.
Why minify here
Smaller CSS means fewer bytes for browsers to download, so pages paint sooner and your styles load faster, especially on mobile connections. Doing it in the browser keeps things quick and private: your code is processed on your own device and never gets uploaded to a server, which matters when the CSS belongs to a client or an unreleased project. It is free, needs no account, and works on any device with a browser.
Keep your original, readable stylesheet for editing and use the minified version only in production. If you also need to shrink HTML or JavaScript, JotTools has matching minifiers for those.
Tip: minified CSS is hard to edit by hand, so always keep an unminified copy as your working source. For squeezing many stylesheets or assets at once, the BulkPro desktop app from the same team handles batch jobs.
Frequently asked questions
- How does the CSS minifier reduce file size?
- It removes comments, extra whitespace and line breaks, and the spaces around braces, colons, semicolons and commas, plus needless trailing semicolons. It is a lightweight minifier, so it never touches your selectors, properties or values. The styling stays identical while the byte count drops.
- Does it show how much I saved?
- Yes. Each pane shows its size in bytes or KB, and the summary line reads out your original size, the minified size and the percent you shaved off, updating live as you type.
- Can I download the minified CSS?
- Yes. Alongside Copy there is a Download button that saves the result as a .min.css file, so you can drop it straight into your project without opening an editor.
- Will minifying change how my CSS works?
- No. The tool only removes characters that browsers ignore (whitespace and comments). Your selectors, properties and values are untouched, so the rendered result is exactly the same.
- Is my CSS uploaded anywhere when I minify it?
- No. Minification runs entirely in your browser on your own device. Your code is never sent to a server, which keeps client work and private projects safe.
- Can I get my original CSS back after minifying?
- Not from the minified output, since comments and formatting are gone for good. Always keep your readable source file and use the minified version only for production.
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Last updated: June 15, 2026