What does this tool do?
JS Beautifier reformats minified or one-line JavaScript into clean, properly indented code, and can also do the reverse by minifying it down to a single line. It runs instantly in your browser and is handy for developers inspecting production bundles, students learning code structure, and anyone debugging a stubborn snippet.
How to use it
- Paste or type your data into the left field.
- The result is generated instantly on the right.
- Use the Copy button to grab the output.
Two directions: beautify and minify
Beautify mode inserts line breaks after braces, brackets, semicolons, and commas, then indents each block with 2 or 4 spaces. Minify mode strips single-line and multi-line comments, collapses whitespace, and tightens the spacing around operators to squeeze code onto one line. The counter at the top shows the change in character count as a percentage, so you can see a result like -40% after minifying.
When it helps
Reach for it when you are trying to read a compressed library pulled from a CDN, when you are a student decoding the shape of a snippet, or when you want to slim down a one-liner you copied. The output copies to the clipboard with a single click so you can paste it straight into your editor. It is built as a fast readability helper, not a full compiler or linter.
Frequently asked questions
Does this replace ESLint or Prettier?
No. Tools like Prettier work on an AST and fully enforce language rules; this is a fast character-based formatter. It is ideal for quick readability, but for enforcing consistent style across a project, use Prettier.
Why only 2 and 4 spaces for indentation?
These are the two most common conventions in the JavaScript community. The Airbnb and Google style guides use 2 spaces, while some older codebases use 4. You can toggle between them while in Beautify mode.
Does minify mode remove comments?
Yes. Both // single-line and /* */ block comments are stripped before whitespace is collapsed. If you want to keep your comments, save a copy of the code before minifying.
Is JS Beautifier free?
Yes. JS Beautifier and all 300+ tools on MagmaNex are completely free with no signup or account required.
Is my data safe?
Yes. Everything runs locally in your browser. The data you enter is never sent to a server, stored, or shared.
Does it work on mobile?
Yes. JS Beautifier works on phones, tablets and desktops — no app download needed.
🔒 Privacy: everything runs in your browser, your data is never sent to a server.