CSS Minifier

How to use CSS Minifier

1. Open CSS Minifier — it runs entirely in your browser with no setup.
2. Paste or type your input into the text area, or upload a file where supported.
3. Set any options you need. The result appears in the output panel — there is no upload step and no waiting on a server.
4. Review the output instantly; large inputs are handled locally without lag.
5. Copy the result to your clipboard or download it. Your data never leaves the page.

Why use CSS Minifier?

• 100% free with no limits, no sign-up and no watermarks.
• Private by design — your data are processed in your browser and never uploaded to a server.
• Fast and lightweight, with instant results even on a phone or a slow connection.
• Works everywhere — any modern browser on Windows, macOS, Linux, Android or iOS.
• Part of a full developer tools suite, so related css minifier tasks are one click away.

What people use CSS Minifier for

• Shrinking a stylesheet before pasting it into a template or a CMS field with a size limit.
• Reducing the size of a small standalone stylesheet that does not go through a build.
• Stripping comments before sharing CSS publicly.

CSS Minifier: limits and things worth knowing

• Comments, redundant whitespace and trailing semicolons are removed. Rule order and specificity are preserved exactly, so rendering does not change.
• Preserve any comment beginning /*! — that convention marks licence headers, and stripping them from third-party CSS can breach the licence.
• As with JSON, gzip already handles most of the repetition, so the real-world transfer saving is much smaller than the raw byte reduction suggests.

Is it private and secure?

Your privacy is built in. CSS Minifier runs completely on your device, so whatever you enter stays in your browser and is never transmitted, logged or stored on any server.

Network activity: none. Nothing is sent and nothing is fetched. This tool makes no network request at all once the page has loaded — which is why it keeps working if your connection drops.

You do not have to take that on trust — our privacy proof page publishes the Content-Security-Policy that enforces it, lists every third party it permits, and shows how to verify the whole claim yourself.

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