Cereio

JavaScript Formatter

Input

Output

Start typing to format your JavaScript

Your formatted JavaScript will appear here

About JavaScript Formatter

Turn compact or irregular JavaScript into consistently indented code, or remove unnecessary whitespace for a smaller result. The tool runs locally and is useful for reading generated scripts, comparing code, and preparing files for development or production.

Key Features

Real-time Formatting

See your JavaScript formatted instantly as you type with live preview.

Beautify & Minify

Switch between readable formatted code and compressed minified output.

Smart Indentation

Properly indents functions, objects, arrays, and control structures.

100% Client-side

All JavaScript processing happens in your browser - your code stays private.

Copy & Download

One-click copy to clipboard or download as a .js file.

ES6+ Support

Handles modern JavaScript including arrow functions, destructuring, and async/await.

How to Use

  1. 1Paste your JavaScript code into the input area on the left.
  2. 2The tool automatically formats your code in real-time.
  3. 3Toggle between 'Beautify' for readable format or 'Minify' for production.
  4. 4Click 'Copy' to copy the output or 'Download' to save as a file.
  5. 5Use 'Clear All' to reset and start fresh.

Pro Tips

  • 💡Minified JavaScript significantly reduces file size - essential for production websites.
  • 💡Use beautified code during development for easier debugging.
  • 💡The formatter preserves your code logic while improving readability.
  • 💡Consider using source maps in production to debug minified code.

Frequently Asked Questions

Is my JavaScript code secure?
Yes! All JavaScript processing happens entirely in your browser. Your code is never uploaded to any server.
Does this tool validate JavaScript syntax?
The formatter will process your code and may show errors for severely malformed syntax. However, it's primarily a formatting tool, not a linter.
Can I format ES6+ JavaScript?
Yes! The formatter fully supports modern JavaScript including arrow functions, template literals, destructuring, classes, async/await, and more.
Does it work with JSX?
This formatter is optimized for standard JavaScript. For JSX (React), the code will be formatted but JSX-specific formatting may not be optimal.
What's the difference between Beautify and Minify?
Beautify adds proper indentation, spacing, and line breaks for readability. Minify removes all unnecessary whitespace and shortens code for smaller file size.