Free JavaScript Formatter & Beautifier 2026
Welcome to Code Formatter JS Formatter – the most reliable and secure tool to format, beautify, and clean up your JavaScript code. Whether you're dealing with minified production code, fixing indentation in legacy scripts, or standardizing code style for your team, our tool uses the industry-standard Prettier engine to deliver perfect results instantly.
Readable code is the foundation of maintainable software. JavaScript, being a flexible language, often accumulates inconsistent formatting – mixed tabs and spaces, missing semicolons, or erratic line breaks. Our JS Beautifier enforces a consistent style guide, making your code easier to read, debug, and share, all primarily client-side for maximum speed and privacy.
How to Use Our JS Formatter Tool
Transform messy JS into clean code in seconds:
- Paste Your Code: Copy your JavaScript snippet or file content and paste it into the "Input JavaScript" pane on the left.
- Click Format: Hit the "FORMAT" button in the footer. The tool uses Prettier to parse and rewrite your code with optimal spacing and structure.
- Review Output: The formatted code appears instantly in the right pane, with 2-space indentation (standard convention) and standardized syntax.
- Copy or Download: Use the copy icon to copy the result to your clipboard or download it as a `.js` file.
Key Features of Our JavaScript Beautifier
We've optimized this tool for professional workflow needs:
- Prettier Integration: We use the same formatting engine used by top tech companies (Facebook, Airbnb) to ensure your code follows modern best practices.
- Syntax Healing: Automatically fixes minor syntax inconsistencies like missing spaces around operators or inconsistent brace positioning.
- ES6+ Support: Fully supports modern JavaScript features including Arrow Functions, Async/Await, Destructuring, and Classes.
- Secure Processing: Your code runs 100% in your browser. We do not store or transmit your scripts to any external server.
- Minified Code Restoration: Perfect for expanding minified/obfuscated code back into a readable, multi-line format for debugging.
Why Formatting JavaScript Matters
Consistent formatting isn't just about aesthetics; it drastically improves development efficiency:
Reduced Cognitive Load
When code follows a predictable visual pattern, your brain spends less time parsing curly braces and more time understanding the logic. Indentation immediately reveals the scope of loops and conditionals.
Bug Prevention
Poor formatting often hides bugs. For example, the famous "goto fail" bug or misleading indentation in `if/else` blocks can be spotted instantly when code is auto-formatted to reflect its actual execution logic.
Smoother Code Reviews
When everyone formats code differently, diffs become cluttered with whitespace changes. Using a standard formatter ensures that version control only tracks significant logic changes, making code reviews focused and fast.
Standardization
Our tool applies a "Standard JS" style – a widely accepted set of conventions that eliminates arguments about semicolons or space-inside-parentheses. It just works.
Common Use Cases for JS Formatting
Developers use our tool daily for various tasks:
Debugging Minified Libraries
If you encounter an error in a third-party library that is minified (e.g., `jquery.min.js`), pasting it here expands it so you can find the line causing the issue.
Cleaning Copied Snippets
Code copied from StackOverflow or blogs often has broken indentation. Run it through our formatter to seamless integration into your project.
Validating Syntax
If the formatter fails or produces unexpected output, it often points to a syntax error (like a missing closing brace) that you missed in your editor.
Learning Best Practices
Beginners can learn proper coding style by writing code and seeing how the formatter reorganizes it. It's like having a senior engineer correct your style instantly.
JavaScript Formatting Best Practices
While tools automate the work, keeping these principles in mind helps:
- Consistent Indentation: Modern JS standard is 2 spaces for indentation. Avoid tabs to ensure code looks the same in GitHub, VS Code, and terminal viewers.
- Semicolons: While ASI (Automatic Semicolon Insertion) exists, explicitly using semicolons prevents edge-case bugs and is preferred in enterprise styles.
- Line Length: Keep lines under 80-100 characters. Our formatter automatically wraps long lines to prevent horizontal scrolling fatigue.
- Object Properties: Consistent spacing in object literals ` { key: value } ` improves readability of data structures.
Frequently Asked Questions
Currently, this tool is optimized for standard JavaScript (ES5/ES6+). While it may format basic TypeScript correctly, complex type annotations might not be handled perfectly. Check back for our dedicated TS tool.
No. Prettier is an AST-based formatter (Abstract Syntax Tree). It rebuilds your code's visual representation without changing its execution logic or AST structure.
JSON is valid JavaScript, so yes, it will format. However, for strict JSON validation and error reporting, we recommend using our JSON Formatter tool.
Yes. The formatting script runs entirely in your browser. No data is sent to our servers, making it safe for proprietary or sensitive code.
The parser includes support for standard ES features used in React. Basic JSX formatting often works out of the box due to Babel support.
It fixes formatting lint errors (spacing, line breaks). It does not fix logic lint errors (like unused variables or undefined functions).
The formatter tries to keep comments near the code they describe. Sometimes, to satisfy line length rules, it might wrap code and move trailing comments to the next line.
Absolutely. JavaScript is JavaScript, whether it runs in the browser or on a server. Paste your Node.js code here to beautify it instantly.
Code Formatter © 2026. Professional developer tools built with privacy and performance in mind.