CSS Minifier

Compress CSS by removing whitespace and comments

🔒 100% ブラウザ内🆓 ずっと無料⚡ サインアップ不要
注意: 下記のツールインターフェースは現時点で英語のみに対応しています。UI の翻訳は順次進めています。 このツールを英語で見る →

使い方

  1. 1
    Paste your CSS

    Drop any CSS - a single rule, a whole stylesheet, or a snippet from DevTools.

  2. 2
    Click minify

    Comments, whitespace, and unnecessary semicolons are stripped instantly.

  3. 3
    Copy the minified output

    Copy the result to your clipboard or see the size reduction stats.

CSS Minifier について

Free online CSS minifier. Strip comments, whitespace, and redundant semicolons from CSS to reduce file size - typically 20-40% smaller. Handy for one-off pastes when you don't want to spin up a full build pipeline. Runs entirely in your browser. 712 Tools の CSS Minifier はモダンな JavaScript API を使って完全にブラウザ内で動作します - サーバーがあなたのデータを見ることは一切ありません。つまり、即時の結果、完全なプライバシー、アップロード制限なしです。

デバッグ、簡単な確認、あるいは本番のインシデント対応まで - このツールは何度でも無料で使えます。ウォーターマークなし、サインアップなし、ツール内広告なし。

よくある質問

How much smaller does CSS get?

Typically 20-40%. Comment-heavy or well-formatted stylesheets shrink more; already-compact CSS shrinks less.

Does it break my CSS?

No. Only whitespace and comments are removed - the CSS grammar is preserved exactly.

Does it support CSS variables and modern syntax?

Yes. Custom properties, nested rules, container queries, and other modern features are preserved intact.

Should I use this in production?

For a real build pipeline, use PostCSS + cssnano or Lightning CSS. This tool is best for quick one-off minification.

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