JavaScript Beautifier
Beautify JavaScript source code into a consistent, readable layout using a browser-loaded parser and formatter.
Format JavaScript with a syntax-aware parser, changing whitespace and indentation.
Processing happens in this browser. Your input is not uploaded or saved.
🔒 All processing happens in your browser — files never leave your device. Your input stays in this browser and is not uploaded to Smart Online Tools.
How it works
- Paste JavaScript source.
- Select Beautify JavaScript.
- Copy the formatted code and run your normal checks.
Good to know: The formatter changes whitespace and may normalize quotes. It does not run the code or check behavior.
Privacy and processing
All processing happens in your browser — files never leave your device. Your input stays in this browser and is not uploaded to Smart Online Tools.
Formatting JavaScript
Consistent formatting makes blocks, function calls, and object literals easier to review. The formatter parses JavaScript before printing it, so malformed input produces a parser error rather than a guessed layout.
The page does not execute pasted code. Keep source maps and build settings in mind if you format generated bundles; your project's configured formatter is usually the best choice for application source.
Frequently asked questions
What does JavaScript Beautifier do?
Format JavaScript with syntax-aware indentation and line breaks. Beautify JavaScript source code into a consistent, readable layout using a browser-loaded parser and formatter.
Does this tool upload my files or input?
Your input stays in this browser and is not uploaded to Smart Online Tools.
What should I know before using this tool?
The formatter changes whitespace and may normalize quotes. It does not run the code or check behavior.