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JavaScript Minifier & Beautifier

Minify JavaScript to reduce file size or beautify it for readability. Supports ES6+ features including arrow functions, template literals, and destructuring. Everything runs in your browser — your code stays private.

 
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What Is JavaScript Minification?

JavaScript minification removes unnecessary characters from your source code without changing functionality. This includes stripping comments, whitespace, and line breaks, plus carefully removing optional semicolons and shortening code where safe. The result is a smaller file that downloads and parses faster.

Minified JavaScript reduces page load time, saves bandwidth, and improves performance on mobile devices. For production websites, minification is essential — even a 200ms improvement in load time can significantly impact user engagement and conversion rates.

When to Minify vs. Beautify

Minify before deploying to production. Modern web apps often serve hundreds of KB of JavaScript. Minifying reduces transfer time, especially on slow mobile connections. Combine with gzip compression for maximum savings.

Beautify when you need to read or debug minified code. If you're inspecting third-party libraries, analyzing production bundles, or reverse-engineering how something works, the beautifier restores human-readable formatting.

Features

How Much Can Minification Save?

Typical JavaScript minification reduces file size by 20-40% depending on coding style and comment density. Well-documented code with lots of whitespace can see 50%+ reductions. When combined with server-side gzip compression, total bandwidth savings of 70-80% are common.

For example, a 100 KB JavaScript file might minify to 60 KB (40% reduction), then compress with gzip to just 20 KB for transmission — an 80% overall reduction in download size.

Minification vs. Obfuscation

This tool performs minification, not obfuscation. Minification removes unnecessary characters but keeps code readable. Obfuscation intentionally makes code hard to understand by renaming variables to short, meaningless names and restructuring logic. For production code, minification is usually sufficient and safer — obfuscation can introduce bugs and makes debugging much harder.

Frequently Asked Questions

What is JavaScript minification?
JavaScript minification removes unnecessary characters like whitespace, comments, and newlines from code without changing its functionality. It reduces file size for faster downloads, improving page load speed and user experience.
How much does JS minification save?
JavaScript minification typically reduces file size by 20-40%. Combined with gzip compression, total savings can reach 60-80%. For large applications with many JavaScript files, this translates to significantly faster page loads.
Should I minify JavaScript in development?
No, keep your source code readable during development and only minify for production builds. Most build tools (Webpack, Vite, esbuild) handle minification automatically as part of the production build process.
Keyboard Shortcuts
Ctrl+Enter Run / Format
Ctrl+Shift+C Copy output
Ctrl+L Clear