CODE FORMATTERS
Free CSS Minifier online
Minify CSS by removing whitespace.
Use CSS Minifier to minify CSS by removing whitespace in seconds, straight from your browser. Paste your file into CSS Minifier, tweak the options, and take the result with one click. CSS Minifier processes everything in your own browser, so your data never leaves your device.
- Free to use
- No signup
- Private and local
- Unlimited use
Why use CSS Minifier
- minify CSS by removing whitespace without installing software
- Your file is processed on your device by CSS Minifier, never uploaded
- CSS Minifier needs no account, email address or payment details
- CSS Minifier shows live output that updates as you type
- CSS Minifier is keyboard accessible and screen-reader friendly
- CSS Minifier is free forever, with no watermark on the result
CSS Minifier runs entirely inside your browser. Your file is never uploaded, stored or shared, and nothing is retained once you close the tab.
How to use CSS Minifier
- Enter your file Paste or type your file into the input panel above.
- Adjust the options Set the options that control how CSS Minifier handles your input.
- Apply the change CSS Minifier works instantly on your device, with no queue and no upload wait.
- Copy or download Copy the output to your clipboard or download it as a file, free and unlimited.
Benefits
Private by design
Your file stays on your device while CSS Minifier works. CSS Minifier never sends it to a server, so confidential work stays confidential.
Instant results
CSS Minifier finishes most jobs in under a second because the work happens on your own hardware.
No signup, no limits
Use CSS Minifier as many times as you want. CSS Minifier asks for no account, adds no watermark and keeps no paid tier gating the output.
Works on any device
CSS Minifier runs in any modern browser on desktop, tablet and phone, with a keyboard-accessible interface throughout.
Who it is for
For developers
Developers use CSS Minifier to debug and ship faster without installing software: minify CSS by removing whitespace on a shared or locked-down machine.
For freelancers
CSS Minifier helps freelancers send client deliverables quickly, since your file never leaves the laptop it was created on.
For support teams
CSS Minifier helps support teams answer customer requests quickly, since your file never leaves the laptop it was created on.
How it works
CSS Minifier loads your file into memory, applies the change you requested to the underlying data rather than to a screenshot of it, and writes a fresh copy for download. Your original stays untouched on disk, and every step of CSS Minifier happens inside your browser sandbox.
Frequently asked questions
Is CSS Minifier free to use?
Yes. CSS Minifier is completely free with no account, no trial and no usage cap. Every feature on this page is available on the first visit.
Does CSS Minifier upload your file to a server?
No. CSS Minifier processes your file inside your browser, so it never reaches a DocTools server. That also means the tool keeps working if your connection drops mid-task.
Is there a limit on how much input I can use?
CSS Minifier handles inputs into the megabytes without trouble; the only real limit is how much your browser tab can hold in memory.
Do I need to install anything to use CSS Minifier?
No installation is needed. CSS Minifier runs in Chrome, Edge, Firefox and Safari, on desktop and on mobile, with no extension or plugin.
Can I use CSS Minifier on a phone or tablet?
Yes. The CSS Minifier interface adapts to small screens and supports touch input, though very large jobs are faster on a desktop browser.
What happens to your file when I close the tab?
It is discarded. CSS Minifier keeps everything in temporary browser memory, so closing the tab removes every trace of the session.
Related tools
- HTML Minifier | Minify HTML by removing whitespace
- JavaScript Minifier | Minify JavaScript code
- JSON Minifier | Minify JSON by removing whitespace
Last updated: 2026-09-07