JavaScript Formatter
Format, beautify and validate your JavaScript code
Input
Output
What is JavaScript Formatter?
Got messy JavaScript code that's hard to read? Minified code that looks like one giant line? This tool fixes that. It takes your JavaScript and makes it beautiful – proper indentation, line breaks, consistent spacing, everything organized. Whether you're debugging, reviewing code, or just trying to understand what your script actually does, this makes it readable.
According to MDN Web Docs, JavaScript is one of the core technologies powering the web. Our formatter follows modern JavaScript standards and best practices, so your formatted code is clean and maintainable.
Best part? Everything happens instantly in your browser. No server uploads, no data storage – just paste, format, and copy. Your code stays private.
What Makes This Tool Different
Pretty Print Instantly
Paste minified or messy JavaScript and get perfectly formatted output in milliseconds. We use consistent indentation and spacing so nested structures are easy to read.
Syntax Validation
While we format, we also check your JavaScript syntax. If something's broken, we'll let you know so you can fix it fast.
Minify Option
Need compact JavaScript for production? One click minifies everything, removing all whitespace while keeping it valid. Perfect for reducing file size.
File Upload Support
Got a big file? Just upload it. Works with .js and .txt files. No need to copy-paste – just drag and drop or click upload.
Copy & Download
One click to copy, or download it as a .js file. Perfect for saving formatted versions or sharing with your team.
Syntax Highlighting
Our editor provides beautiful syntax highlighting. Keywords, strings, functions, and variables are color-coded for easy reading.
How It Works
Paste or Upload JavaScript
Paste your JavaScript code into the left editor, or click "Upload" to load a file. You can also click "Sample" to see example JavaScript. The tool accepts any JavaScript code – ES5, ES6+, modern syntax, you name it.
Automatic Formatting
As soon as you paste, the formatter processes your JavaScript and displays the beautifully formatted version on the right. Functions get proper indentation, nested structures are clearly separated, and everything is aligned perfectly.
Copy or Download
Click "Copy" to copy the formatted JavaScript to your clipboard, or "Download" to save it as a file. Need minified JavaScript instead? Click "Minify" to compress it. All processing happens instantly in your browser.
When You'd Actually Use This
Code Review
Reviewing minified or messy code? Format it first to see the structure clearly. Makes it easier to spot bugs, understand logic, or provide feedback to teammates.
Debugging
Trying to debug minified production code? Format it first to make it readable. Much easier to set breakpoints and understand what's happening when the code is properly formatted.
Learning JavaScript
New to JavaScript? Formatting helps you understand the syntax. See how functions nest, how objects work, and how code structures are organized. Much easier than reading minified code.
Legacy Code Maintenance
Working with old, unformatted code? Format it to make it maintainable. Proper indentation and spacing make it way easier to understand and modify.
Common Questions
Is my code stored?
No. All formatting happens in your browser using JavaScript. Your code never leaves your computer.
What JavaScript versions are supported?
We support all modern JavaScript syntax – ES5, ES6+, async/await, arrow functions, classes, modules, you name it. If it's valid JavaScript, we can format it.
Can I format invalid JavaScript?
We'll try to format it, but if there are syntax errors, the output might not be perfect. Fix syntax errors first for best results.
What indentation does it use?
We use consistent spacing for indentation, making nested structures easy to read. The exact style follows common JavaScript formatting conventions.
How big can my file be?
Since processing happens in your browser, performance depends on your device. Small files format instantly. Very large files (several MB) might take a few seconds, but they'll still work.
Can I customize the formatting?
Currently, we use standard formatting conventions. If you need specific formatting options, consider using command-line tools like Prettier for advanced customization.
Other JavaScript Tools You Might Need
Formatting is just one JavaScript task. Here are other tools that work well together:
Need to learn more about JavaScript? Check out the comprehensive guide on MDN or the official ECMAScript specification.