Use this JavaScript Minifier & Beautifier to optimize JS for production or format JS for readability. Minifying removes unnecessary characters like whitespace and comments, which reduces file size and improves page load performance. Beautifying does the reverse: it formats code with indentation and line breaks so you can read and debug minified scripts.
You can also remove console statements and apply basic variable mangling. Console removal is useful for production, but it should be used carefully if your code relies on logs for monitoring or error reporting. Variable mangling can reduce size further, but it may break code if you depend on specific global or public names. Paste your script, choose an operation, then copy or download the output. For debugging production issues, keep source maps in your build pipeline.
Format and Optimize JavaScript Code
Operation
Options
Input JavaScript
Output JavaScript
What this tool does (and doesn’t)
Does
- Minify JS by removing whitespace and comments
- Beautify JS for readability
- Optionally remove console statements
- Optionally apply basic variable mangling (demo)
Does not
- Bundle modules (this is not Webpack/Vite/Rollup)
- Transpile TypeScript/JSX or downlevel modern JS
- Tree-shake unused code
- Generate source maps
How to minify or beautify JavaScript
- Paste JavaScript into Input JavaScript (or upload a .js file).
- Select Minify or Beautify.
- Choose options (remove comments/whitespace/console, or formatting settings).
- Click the action button.
- Copy or download the output.
JavaScript minifier examples (before and after)
Example: Minify JavaScript
// Greeting function hello(name) { console.log("Hello", name); return "Hello " + name; }
function hello(n){return"Hello "+n}
Example: Beautify JavaScript
(()=>{const a=1;function f(x){return x+a}console.log(f(2))})()
(() => { const a = 1; function f(x) { return x + a; } console.log(f(2)); })();
Best practices
- Keep readable source code for development; minify only for production.
- If you use a build pipeline (Vite/Next/Webpack), minify there and keep source maps.
- Don’t enable variable mangling unless you test the output carefully.
- Be careful with “Remove Console” if your app uses console logging for monitoring.
- If your code uses ES modules, consider a modern minifier like Terser in a build pipeline.
Troubleshooting
| Problem | Likely cause | Fix |
|---|---|---|
| Minified output breaks | Mangling renamed something important | Disable mangling or protect reserved/public names |
| import/export fails | Module syntax not handled | Use a modern minifier like Terser via a build tool |
| Regex behaves differently | Edge-case parsing | Validate input and test output (prefer build tools for complex code) |
| Script depends on whitespace hacks | Rare legacy patterns | Avoid whitespace removal for that file |
| Debugging is painful | No source maps | Keep source maps in production builds |
Common questions
What is the difference between minifying and uglifying?
Minifying usually means removing whitespace/comments to reduce size. “Uglifying” often also includes variable/function renaming (mangling) and other transformations that can make code harder to read.
Is removing console.log safe?
It can be safe for production, but use it carefully if your app relies on console logs for monitoring, debugging, or error reporting. Always test the minified output.
What is variable mangling and when should I use it?
Variable mangling renames identifiers to shorter names to reduce size. It can break code if you depend on public/global names, so enable it only after testing (and ideally in a real build pipeline).
Why does minified code break sometimes?
Common causes include invalid input syntax, regex edge cases, module syntax that a minifier doesn’t handle, or unsafe transformations like mangling reserved/public names.
Does this tool support ES modules (import/export)?
This tool is designed for quick formatting and basic minification. For complex modern builds (modules, bundling, source maps), use a build tool like Terser via Vite/Webpack/Next.
Should I use this tool or a build tool like Terser?
For production, a build pipeline with Terser (and source maps) is best. This tool is ideal for quick one-off minify/beautify tasks and debugging.
What are source maps and why do they matter?
Source maps map minified production code back to your original source, making debugging much easier. If you ship minified JS, keeping source maps in your pipeline helps investigate errors.
Can I beautify an obfuscated script?
Beautifying can improve readability, but it won’t “de-obfuscate” logic. Obfuscated scripts may remain hard to understand even after formatting.
Can this tool minify inline JavaScript?
Yes. Paste your inline script, minify it, then copy the output back into your HTML/template.
How do I minify JavaScript for WordPress without breaking plugins?
Avoid double-minifying (plugin + tool). If a plugin breaks, exclude that script from minification, or use safe settings and test carefully.
Related tools
- CSS Minifier — minify/beautify CSS for front-end performance
- JSON Formatter — pretty-print and validate JSON payloads
- Base64 Encoder/Decoder — encode data for transport and embedding
- Hash Generator — hash scripts or artifacts for integrity checks