JavaScript Formatter
Beautify and format messy or minified JavaScript with clean indentation, consistent spacing, and one statement per line. Runs entirely in your browser.
Format and Beautify JavaScript Online
This JavaScript formatter turns minified, single-line, or inconsistently indented code into clean, readable source. Paste any snippet and it is re-indented instantly with consistent spacing, predictable brace placement, and one statement per line — the kind of layout that makes a function easy to read in code review or to drop into a tutorial. Everything happens in your browser, so even proprietary code never leaves your machine.
Why beautify JavaScript?
Code arrives in unreadable shapes for all sorts of reasons: it was downloaded from a production bundle, copied out of a browser dev-tools panel, generated by a build step, or simply written in a hurry. A consistent format is not cosmetic — it reduces the cognitive load of reading logic, makes diffs smaller and more meaningful, and surfaces structural mistakes such as a misplaced brace or an accidentally nested block. Reformatting before you commit also keeps a team's codebase visually uniform regardless of who wrote each line.
How this beautifier works
The tool is powered by js-beautify, the same well-tested engine used by many editor plugins, so it understands real JavaScript syntax rather than guessing with regular expressions. It correctly handles strings, template literals, regular-expression literals, comments, arrow functions, and modern ES syntax — it will not break a regex that contains a slash or mangle a string that contains a brace. Choose your indentation style — 2 spaces, 4 spaces, or tabs — to match your project's conventions, and the output updates as you type.
What it does and does not change
Beautifying is purely a layout operation. The formatter rewrites whitespace, indentation, and line breaks; it never renames a variable, removes a statement, or alters what your code does. The behaviour of the formatted output is identical to the input. If your goal is the opposite — shrinking code for production rather than expanding it for reading — use the companion JavaScript minifier instead.
Tips for clean results
For the most readable output, format one logical file or module at a time rather than concatenating unrelated snippets. If you are pasting code from a minified bundle, expect long chained expressions to remain long — beautifying adds structure but will not split a single complex statement into several. Pair this tool with a linter for catching logic issues; the formatter handles presentation, the linter handles correctness. Because the formatting is deterministic, running the same code through it twice always yields the same result, which makes it safe to use as a quick pre-commit cleanup step or to standardise code samples before pasting them into documentation, a blog post, or a bug report.
Format and Beautify JavaScript Online
This JavaScript formatter turns minified, single-line, or inconsistently indented code into clean, readable source. Paste any snippet and it is re-indented instantly with consistent spacing, predictable brace placement, and one statement per line — the kind of layout that makes a function easy to read in code review or to drop into a tutorial. Everything happens in your browser, so even proprietary code never leaves your machine.
Why beautify JavaScript?
Code arrives in unreadable shapes for all sorts of reasons: it was downloaded from a production bundle, copied out of a browser dev-tools panel, generated by a build step, or simply written in a hurry. A consistent format is not cosmetic — it reduces the cognitive load of reading logic, makes diffs smaller and more meaningful, and surfaces structural mistakes such as a misplaced brace or an accidentally nested block. Reformatting before you commit also keeps a team's codebase visually uniform regardless of who wrote each line.
How this beautifier works
The tool is powered by js-beautify, the same well-tested engine used by many editor plugins, so it understands real JavaScript syntax rather than guessing with regular expressions. It correctly handles strings, template literals, regular-expression literals, comments, arrow functions, and modern ES syntax — it will not break a regex that contains a slash or mangle a string that contains a brace. Choose your indentation style — 2 spaces, 4 spaces, or tabs — to match your project's conventions, and the output updates as you type.
What it does and does not change
Beautifying is purely a layout operation. The formatter rewrites whitespace, indentation, and line breaks; it never renames a variable, removes a statement, or alters what your code does. The behaviour of the formatted output is identical to the input. If your goal is the opposite — shrinking code for production rather than expanding it for reading — use the companion JavaScript minifier instead.
Tips for clean results
For the most readable output, format one logical file or module at a time rather than concatenating unrelated snippets. If you are pasting code from a minified bundle, expect long chained expressions to remain long — beautifying adds structure but will not split a single complex statement into several. Pair this tool with a linter for catching logic issues; the formatter handles presentation, the linter handles correctness. Because the formatting is deterministic, running the same code through it twice always yields the same result, which makes it safe to use as a quick pre-commit cleanup step or to standardise code samples before pasting them into documentation, a blog post, or a bug report.
You build the idea. I'll ship the product.
Productized MVP development for founders. 9 SaaS apps shipped — yours could be next, in 6 weeks. Secure by default.
Frequently Asked Questions
Common questions about the JavaScript Formatter
A JavaScript formatter, also called a beautifier, rewrites the layout of your code so it is easy to read. It adds consistent indentation, puts one statement per line, and applies predictable spacing around operators and braces. It changes only whitespace and line breaks — your code's behaviour is completely unchanged.
No. Beautifying is purely a presentation operation. The tool never renames variables, removes statements, or alters logic — it only adjusts indentation, spacing, and line breaks. The formatted output behaves identically to the input.
Yes. Pasting minified, single-line JavaScript is the most common use. The formatter expands it back into readable, indented source so you can study or debug a production bundle. Note that very long chained expressions stay on one logical line — beautifying adds structure but does not split a single complex statement into several.
No. Formatting runs entirely in your browser using JavaScript. Nothing you paste is sent to a server, so it is safe to use with proprietary or sensitive source code.
Yes. You can format with 2-space indentation, 4-space indentation, or tabs to match your project's style guide. The output updates instantly when you change the setting.
Explore More Tools
Continue with these related tools
ℹ️ Disclaimer
This tool is provided for informational and educational purposes only. All processing happens entirely in your browser - no data is sent to or stored on our servers. While we strive for accuracy, we make no warranties about the completeness or reliability of results. Use at your own discretion.