CSS Compressor | Quintaphon Docs

Minify CSS with CSSO in a full-tab editor. Beautify input or output, view compression stats, and copy or download results, all locally in your browser.

TIP

Beautify messy source CSS before editing, then turn beautify off and compress for the smallest output.

Getting started

Install CSS Compressor and click the toolbar icon.
A dedicated editor tab opens (there is no popup).
Paste CSS into the source panel and click Compress.
Copy or Download the minified output, or toggle beautify to inspect formatting.

Editor layout

The editor is split into source and output areas with a control bar between them:

Source CSS textarea with an optional beautify checkbox.
Compressed Output read-only textarea, also beautifyable for review.
Actions: Compress, Copy, Download, Clear All.
Stats row: original size, compressed size, savings percentage, and process time in milliseconds.
Header icons: theme toggle, help link, and Quintaphon branding.

Compression

Compression runs through the bundled CSSO engine (csso.minify()). Valid CSS minifies in one click; syntax errors appear inline in the output panel so you can fix and retry. Download saves as minified.css.

Beautify toggles

Each beautify checkbox snapshots the current raw text, then shows a formatted view (2-space indent via js-beautify). Unchecking restores the snapshot. If you type while beautify is on, the toggle turns off automatically so you do not lose edits.

Theme

Dark and light themes are available from the moon/sun toggle. Preference is stored in localStorage as cc-theme-preference. When unset, the editor follows your system prefers-color-scheme setting.

Features

CSSO minification: One-click compress with size and time stats.
Beautify toggles: Independently format input or output with js-beautify.
Compression stats: Original size, compressed size, savings %, and milliseconds.
Copy and download: Export minified CSS to clipboard or .css file.
Theme support: Dark/light toggle with system preference fallback.
Toolbar launcher: Opens the full-page editor in a new tab.

Privacy

Your CSS never leaves the extension tab. No network requests are made during compress or beautify.

See the Apps & Extensions Policy and Privacy Policy for company-wide details.

Need help?

Syntax errors show inline in the output panel; fix invalid CSS and compress again. Very large stylesheets may take longer to process on low-end machines.