JavaScript Minifier
JavaScript minification removes whitespace, comments, and shortens variable names to reduce file size. A 100KB script minifies to ~50KB, reducing load time and bandwidth. Minification preserves functionality while uglification also obfuscates code. Tools use AST parsing for safe transformations. For example, "function calculateSum(a, b) { return a + b; }" becomes "function c(a,b){return a+b}". Always keep source maps for debugging. Use Terser, UglifyJS, or build tools (Webpack, Vite). Combine with gzip compression for 70-80% total size reduction.
Minify or beautify JavaScript code online. Remove whitespace, comments, and unnecessary characters to reduce file size, or format minified code for readability. Real-time processing with syntax highlighting.
JavaScript Input
How to Use
- Enter your value in the input field
- Click the Calculate/Convert button
- Copy the result to your clipboard
Frequently Asked Questions
- What does a JavaScript minifier do?
- A JavaScript minifier reduces file size by removing whitespace, comments (both single-line // and multi-line /* */), and unnecessary characters from your code. The minified code is functionally identical to the original — it runs exactly the same way in the browser, but loads faster because there are fewer bytes to download.
- Does minifying JavaScript break my code?
- Simple minification (removing whitespace and comments) does not break your code. It preserves all variable names, string literals, and logic. However, advanced techniques like variable renaming (uglification) require AST parsing and can sometimes cause issues with eval() or dynamic property access. This tool only performs safe whitespace and comment removal.
- What is the difference between minify and beautify?
- Minify compresses JavaScript by removing all unnecessary whitespace, line breaks, and comments to produce the smallest file possible. Beautify (also called prettify or format) does the opposite — it adds proper indentation, line breaks, and spacing to make code human-readable. Minified code is used in production; beautified code is used during development.
- How much file size reduction can I expect from minification?
- Typical JavaScript minification reduces file size by 20-60%, depending on coding style. Code with many comments, generous whitespace, and long variable names will see larger reductions. Already compact code will see smaller gains. Combining minification with gzip compression on the server can achieve 70-90% total reduction.
- Should I minify JavaScript for production?
- Yes, minifying JavaScript is a best practice for production websites. It reduces file size, improves page load times, saves bandwidth, and improves Core Web Vitals scores. Most build tools (Webpack, Vite, esbuild) include minification as part of the production build process. Always keep unminified source code for development and debugging.
- What is the difference between minification and obfuscation?
- Minification removes whitespace and comments to reduce file size while keeping code readable if formatted. Obfuscation intentionally makes code hard to understand by renaming variables, encoding strings, and altering control flow. Minification is for performance; obfuscation is for intellectual property protection. This tool only performs minification.