CSS Minifier

A CSS minifier compresses a stylesheet by removing every byte that the browser does not need to render the page: spaces, tabs, line breaks, and comments. The CSS that is comfortable for a developer to write is full of indentation and explanatory comments, but the browser ignores all of it. Stripping that whitespace produces a functionally identical file that downloads faster, which directly improves page load time and Core Web Vitals. This tool removes redundant whitespace, collapses the stylesheet, and deletes comments, while preserving comments that begin with the /*! marker. That marker is the long-standing convention for license headers and legal attributions that must survive minification, so license notices stay intact. After minifying it shows the original size, the minified size, and the percentage saved so you can see the impact. A realistic expectation matters here. The savings come almost entirely from whitespace and comment removal, so heavily commented and deeply indented source shrinks the most, while already-compact CSS barely changes. This tool does not perform the deeper optimizations a build-time tool like cssnano does: it does not merge duplicate selectors, shorten hex colors (#ffffff to #fff), collapse longhand into shorthand, or remove unused rules. It is a fast, safe whitespace-and-comment minifier, not a full optimizer, which is exactly what you want when you need a quick production file without spinning up a build pipeline. Because all processing happens in your browser, your CSS is never uploaded, so proprietary or client stylesheets stay private. For the reverse operation, the CSS Beautifier expands a minified file back into readable form.