What is code minification?

Code minification is the process of removing unnecessary characters from source code without changing its functionality. This includes stripping whitespace, comments, and redundant syntax. Minified code is smaller, loads faster over the network, and improves website performance metrics like Core Web Vitals.

Is my code sent to a server?

No. All minification happens entirely in your browser using JavaScript. Your code never leaves your device, is never transmitted over the network, and is never stored anywhere. You can even disconnect from the internet after the page loads and it will still work.

What's the difference between HTML, JS, and CSS minification?

HTML minification removes comments, collapses whitespace between tags, and can optionally remove optional end tags. JS minification strips comments and unnecessary whitespace while preserving string literals and regex patterns. CSS minification removes comments, collapses whitespace, and tightens spacing around braces, colons, semicolons, and commas.

Will minification break my code?

This tool uses conservative regex-based minification that is safe for most code. It preserves string contents, template literals, and regex patterns in JavaScript. However, for production builds we recommend using dedicated tools like Terser (JS), cssnano (CSS), or html-minifier-terser (HTML) for more thorough and AST-aware optimization.

Does minification preserve inline CSS and JS inside HTML?

This tool processes each language independently. If you paste HTML, only the HTML is minified — inline CSS in tags and JS in tags are preserved as-is. For full optimization of inline code, minify each language separately.

How much size reduction can I expect?

Typical reduction ranges from 20-50% depending on the code. HTML with lots of comments and whitespace can see 30-40% reduction. JavaScript and CSS typically see 25-50% reduction. The exact savings depend on how verbose the original code is and which options you enable.

Can I reverse minified code back to readable form?

No, this tool does not include a beautify/unminify feature. Minification is a lossy process — whitespace and comments are removed permanently. To restore readability, use a dedicated code formatter or beautifier tool for your specific language.

Is there a file size limit?

The practical limit depends on your device's available memory. Most files under 5-10 MB work smoothly in modern browsers. Extremely large files may cause sluggishness. For those cases, use command-line tools like Terser, cssnano, or html-minifier-terser instead.

Tools

OptionsRemove CommentsCollapse WhitespaceRemove Optional Tags

Input

Output

Minified code will appear here

Code Minifier — Minify HTML, CSS & JavaScript Online

Free online code minifier for HTML, CSS, and JavaScript. Compress and optimize your code by removing whitespace, comments, and unnecessary characters. Reduce file size, improve page load speed, and boost Core Web Vitals. Features include language auto-detection, copy to clipboard, one-click download, real-time size stats with compression ratio. 100% client-side processing — your code never leaves your browser.

Features

✓Minify HTML, CSS, and JavaScript in one unified tool — no need to switch between different sites
✓Automatic language detection — paste any code and the tool identifies HTML, CSS, or JS automatically
✓Remove comments (HTML , JS // and /* */, CSS /* */) to strip unnecessary bytes
✓Collapse whitespace — eliminate extra spaces, tabs, and line breaks for compact output
✓Real-time size comparison with original vs minified size and compression ratio percentage
✓One-click copy to clipboard and download as .html, .min.js, or .min.css file
✓Detailed statistics including bytes saved, compression ratio, and character count
✓Support for large files with browser-native processing — no file upload limits
✓100% client-side processing — your source code never leaves your browser
✓Dark mode compatible with clean, minimal interface optimized for developer workflow

How to Use

1Select your language tab — HTML, JavaScript, or CSS — or paste code and let auto-detect choose for you
2Paste or type your code into the input editor. You can also load an example using the sample buttons above the editor
3Configure minification options: toggle Remove Comments and Collapse Whitespace on or off
4Click the Minify button — your minified code appears instantly in the output panel with size statistics
5Copy the minified output to your clipboard with one click, or download it as a file using the Download button

Frequently Asked Questions

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