JavaScript Formatter
Beautify and format JavaScript code online — formats messy or minified JS into readable, indented code. 100% client-side, no upload required.
JavaScript Input
How to format JavaScript online
- Paste your JavaScript into the input area — minified, messy, or a copied snippet.
- Choose an indent size (2 or 4 spaces).
- Click Format JavaScript to beautify the code.
- Copy the output or download it as a
.jsfile.
Privacy — your code never leaves your device
This JavaScript formatter runs entirely in your browser using client-side JavaScript string processing. Your code is never sent to any server, never stored, and never shared. It is the ideal tool for formatting private, proprietary, or sensitive JavaScript code without worrying about data leaks or upload policies.
What this formatter does
The JavaScript formatter adds proper indentation based on brace depth, inserts newlines after statements and block closings, and preserves string literals, template literals, and comments exactly as written. It handles common patterns including functions, classes, arrow functions, async/await, try/catch/finally, and if/else chains. It is designed to make minified or compacted JavaScript human-readable — useful for debugging, code review, or understanding third-party snippets.
This tool formats JavaScript code as text only. It does not run, execute, or evaluate your code under any circumstances. No eval, no Function constructor, no iframe execution — your code is treated as a plain text string throughout.
Frequently Asked Questions
Does this upload my JavaScript code?
No. Everything runs inside your browser tab using plain JavaScript string processing. No network request is made and your code never leaves your device. This is a private, browser-based JavaScript formatter with no signup required.
Does this tool run or execute my JavaScript?
No. This tool formats JavaScript code as text in your browser. It does not run, execute, or evaluate your code. There is no use of eval(), new Function(), or any JavaScript execution mechanism. Your code is processed purely as a string.
Can this format minified JavaScript?
Yes — formatting minified JavaScript is the primary use case. Paste the minified one-liner and the formatter will rebuild indentation and line breaks based on brace structure and statement boundaries, making it readable for debugging or review. Very large minified files (hundreds of KB) may take a moment.
What is the difference between a JavaScript Formatter and JavaScript Minifier?
A JavaScript formatter (also called a JS beautifier or JS prettifier) expands compact code into a human-readable, indented format — adding whitespace for clarity. A JavaScript minifier does the opposite: it removes comments and unnecessary whitespace to produce the smallest possible file for production use. Use the formatter to read code, the minifier to deploy it.
Why did my code not format correctly?
This formatter uses a brace-depth heuristic rather than a full parser, so complex patterns like regex literals containing braces, deeply nested template literal expressions, or unusual minifier output may not format perfectly. For production-grade formatting, consider using Prettier locally. This tool is designed for quick, private, no-install beautification of common JavaScript patterns.