Beautify and prettify JavaScript with consistent indentation and spacing. Runs entirely in your browser.
How to use the JS Formatter
Paste your JavaScript into the input box.
Pick the indent size you want.
Copy the beautified result.
This is a JavaScript beautifier that reformats minified or messy code with consistent indentation, spacing and line breaks, so it becomes readable again for understanding or debugging.
It is powered by a well-established formatting engine, the same kind of logic editors use, so it handles modern JavaScript syntax and produces clean, conventional output rather than a naive reindent.
Formatting runs entirely in your browser, so your code never leaves your device, which matters for proprietary or sensitive scripts.
Reformatting only changes layout, never behavior. The tool rearranges whitespace and line breaks; it does not rename variables, remove code or alter logic, so the script does exactly what it did before, just laid out clearly.
Because JSON is valid JavaScript syntax, you can also paste a JSON object or array and get it cleanly indented, which is handy when you have a blob of data rather than code.
It beautifies rather than minifies. Safe minification needs a full parser to rename and drop code without changing behavior, so this tool focuses on making code readable rather than smaller.
Frequently asked questions
No, it only beautifies. Safe JavaScript minification needs a full parser to rename and drop code without changing behaviour, so this tool focuses on making code readable rather than smaller.
Yes. JSON is valid JavaScript syntax, so pasting a JSON object or array formats it cleanly with proper indentation.
No. Formatting runs entirely in your browser, so your code never leaves your device, which is important for proprietary or sensitive scripts.
No. It only adjusts indentation, spacing and line breaks. It does not rename, remove or rewrite logic, so the script behaves exactly as before.
No. It reformats the code you give it for readability but does not correct bugs or syntax errors; it simply lays the existing code out cleanly.
Embed this tool
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<iframe src="https://monu.tools/embed/en/javascript-formatter" width="100%" height="640" style="border:1px solid #e5e5e5;border-radius:12px;max-width:680px" loading="lazy" title="Monu Tools"></iframe>Related tools
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