How to Use JavaScript Formatter

1

Paste your JavaScript into the input box, whether it is minified, partially obfuscated, or hand-mangled.

2

Set the indent width to 2 or 4 spaces and pick a brace style that matches your project.

3

Click the "Process" button to re-indent the code and place each statement on its own line.

4

Copy the beautified script, or download it and run it through your linter and tests before shipping.

Features

Understands template literals, regex literals, and nested ternaries

Keeps comments in place and indents them with the code they document

Handles arrow functions, async and await, classes, and destructuring

Reads minified and bundled JavaScript back into a workable shape

Configurable indent width and brace style to match your codebase

Entirely client-side, so unreleased front-end code is never sent anywhere

Frequently Asked Questions

No. Prettier and the ESLint fixer handle project-wide conventions, import ordering, and lint rules as part of a real workflow. This tool is for the one-off case: reading a snippet or a bundled file right now without setting anything up.

It will not, because the tool only changes whitespace and line breaks. JavaScript uses automatic semicolon insertion and the formatter accounts for it, so a reformatted file parses to exactly the same token stream and the same abstract syntax tree.

Plain ES5 through modern syntax is handled, including classes, generators, and optional chaining. JSX, TypeScript type annotations, and experimental decorators sit outside the ECMAScript grammar this formatter targets, so those files are best taken through a real compiler.

Yes, free with no account, no watermark, and no practical cap on file size. Very large bundles simply take a moment to parse, and everything happens in your browser rather than being uploaded.

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About JavaScript Formatter

Production JavaScript arrives minified, and a single line of 200,000 characters is not something you can debug. The JavaScript Formatter parses your code and re-prints it with proper indentation, putting every statement on its own line and every block brace on its own line so the control flow is visible again.

JavaScript has a few syntax traps that naive reformatters fall into. Regex literals versus division, template literals containing braces and expressions, and semicolon-free code all require real parsing rather than pattern matching. Those are handled here, so a line that looks like a broken regex is left intact and a nested template literal keeps its structure.

Comments are kept and indented alongside the code they document, which matters when you are trying to work out why a bundled function behaves differently from the source you wrote. Indent width and brace style are both configurable. This is a readability tool, not a compiler: it changes whitespace, never tokens, so behaviour is identical.

When to Use This Tool

Reading a third-party or bundled script you need to understand quickly
Reverse engineering a snippet from a browser script tag
Formatting code for a tutorial, blog post, or Stack Overflow answer
Comparing two builds of a script line by line
Cleaning up code generated by a template or string concatenation helper

JavaScript Formatter

Result

Results