Free Online CSS, JavaScript & HTML Minifier

Instantly minify your CSS, JavaScript, and HTML code with our free online tool. Reduce file sizes by removing comments, unnecessary whitespace, and redundant characters. Includes a beautify mode for reformatting compressed code. No signup, no data sent to servers — everything runs in your browser.

Features

CSS Minifier — Removes comments, collapses whitespace, strips redundant semicolons, and compresses selectors
JavaScript Minifier — Safely removes comments (single-line and multi-line), collapses whitespace while preserving string literals
HTML Minifier — Strips HTML comments, collapses whitespace between tags, removes unnecessary quotes
Beautify / Format Mode — Reverse of minify: reformat compressed CSS, JS, or HTML with proper indentation
Size Comparison — See original vs. minified sizes with percentage saved
Copy & Download — One-click copy to clipboard or download as a file
Drag & Drop Upload — Load files by dragging onto the editor
Dark & Light Theme — Toggle for comfortable editing

How to Use

Select the language tab: CSS, JavaScript, or HTML
Paste your code into the input panel, or drag & drop a file
Click Minify to compress, or Beautify to format
Review the size comparison, then Copy or Download the result

Frequently Asked Questions

Is my code safe?

Yes. All processing happens entirely in your browser using JavaScript. No code is uploaded to any server. Your source code never leaves your machine.

How much space can minification save?

Typically 20-60% depending on the original formatting. Well-commented and indented files see the biggest reductions. Combined with gzip compression on your server, you can achieve 80-90% total reduction.

Is the JavaScript minifier safe to use?

Our JS minifier performs safe transformations only: removing comments and collapsing whitespace. It does not rename variables, remove dead code, or perform tree-shaking. For production builds, consider pairing this with a build tool like Terser or esbuild.

What is the Beautify mode?

Beautify is the opposite of minify. It takes compressed, single-line code and reformats it with proper indentation and line breaks, making it readable again. This is especially useful for CSS and HTML.

Can I minify large files?

Yes. The minifier handles files up to several megabytes in the browser. For very large production codebases, consider command-line tools integrated into your build pipeline.