JS Beautifier
Format and beautify your JavaScript code with customizable indentation. Minify option for production.
How to Use Js Beautifier
Follow these simple steps to get the best results.
Paste your JavaScript
Input minified or poorly formatted JS code from your project or a third-party library.
Format and structure
Click Format to auto-indent, add line breaks, and organize functions and blocks clearly.
Copy formatted JS
Get clean, readable JavaScript code that supports ES6+ syntax including arrow functions.
Frequently Asked Questions
Everything you need to know about Js Beautifier.
About the Js Beautifier Tool
Analyze and de-minify JavaScript with the ToolFlic JS Beautifier. Minified JS is often unreadable, with shortened variable names and no whitespace. While our tool can't restore variable names, it can restore the structure, adding indentation and line breaks to make the logic of the code easy to follow.
Core Advantages
Debug complex scripts or analyze external libraries with ease. By restoring the visual hierarchy of the code, you can more easily spot logic flow, conditional statements, and function calls. It's a favorite tool for security researchers and curious developers.
Architecture & Security
Our beautifier uses a sophisticated JavaScript tokenizer that identifies blocks, loops, and expressions. It applies industry-standard indentation rules to ensure the code is clear and professional-looking, all while running entirely in your secure browser environment.
Under the Hood: the Js Beautifier explained properly
No marketing filler — just the mechanics, the trade-offs and the real limits, explained clearly.
How it actually works
Formatting is done by js-beautify 1.14.0, the reference beautifier for JavaScript, so brace placement, statement breaks, chained calls and object literals are laid out with real syntax awareness rather than by counting indentation characters. Indentation is 2, 4 or 8 spaces, and a minify switch produces the compact single-line form.
Because the library tokenises the source, string contents, regular-expression literals and comments are treated as opaque text and are never re-flowed inside, which is what separates a beautifier from a search-and-replace.
What that means for your results
A beautified script is behaviourally identical to the input: no identifier is renamed, no statement is reordered, no semicolon is inserted in a way that changes meaning. That makes it safe to run on a file you are about to read rather than reason about.
Automatic indentation is also the quickest way to see where a block actually closes in a script someone else wrote, which is usually the real reason the file is unreadable.
Where it falls short — honestly
It formats rather than parses strictly: unusual syntax may be laid out oddly, and a file that is not valid JavaScript can come back looking tidy while still being broken. It also will not reflow minified code that lost its identifiers - the output of a mangler is compact but the names stay short.
Line-length preferences, brace style options and linting rules are not exposed here; the library's defaults apply. Code style enforcement belongs in a linter wired into your build.
A real end-to-end workflow
Paste a one-line bundle fragment from a browser console to see its structure, or reformat a script that has drifted across several editors before committing it.
For the opposite direction use JS Minifier, which is a separate, region-aware engine rather than this tool's compact switch; for markup and styles around the script there are HTML Beautifier and CSS Beautifier.
Browse more Developer Tools
View All Developer →Your Privacy is Our Core Mission
We've built this utility specifically to protect your digital footprint. Every byte of data is processed locally within your browser — it never touches our servers. That is our absolute guarantee.
Designed for productivity, optimized for security. We know how critical 💻 are, and we're here to make them seamless and safe.
