JavaScript Beautifier, Format JS, TS, JSX & TSX Online
Paste minified or messy JavaScript and get clean, readable, syntax-aware code instantly. Real Prettier options (semicolons, single vs double quotes, tab width, print width and trailing commas) all client-side, nothing uploaded.
What is the javascript beautifier?
Formatting JavaScript, TypeScript, JSX and TSX with the Prettier engine, the JavaScript Beautifier turns minified or messy code into clean, syntax-aware output. Control semicolons, single versus double quotes, tab width, print width and trailing commas. Free and fully client-side. Nothing is uploaded, and everything runs in your browser.
The GigAI JavaScript Beautifier is a desktop-grade code formatter that reformats JavaScript, TypeScript, JSX and TSX using Prettier's real parser. Not a regex that just adds newlines. Paste a one-line minified bundle, an unreadable snippet from a Stack Overflow answer, or a diff-noisy file, and it rebuilds the code with consistent indentation, spacing and line wrapping in a fraction of a second. Unlike toy beautifiers that only re-indent, this understands the syntax tree, so template literals, arrow functions, JSX, decorators, optional chaining and modern ES2022+ features all come out correct. You get the exact style controls teams fight over in code review: semicolons on or off, single or double quotes, 2 / 4 / 8-space or tab indentation, a configurable print width that decides where long lines wrap, and trailing-comma style (none, ES5 or all). It auto-detects TypeScript and JSX so you rarely have to pick a language, but you can override it. When the input has a genuine syntax error, it surfaces the precise line and column Prettier choked on so you can fix it rather than staring at a silent blank pane. Everything happens locally in your browser, your proprietary source, API keys embedded in config, or client code is never uploaded, logged or seen. Close the tab and it's gone.
- Difficulty:
- Easy
- Typical time:
- ~15s
- Processing:
- 100% browser processing
Last updated
How to use the javascript beautifier
- 1
Paste, drop or import your code
Paste into the left editor, drag a .js / .ts / .jsx / .tsx file onto it, or click to browse. Or load a built-in sample to try it instantly.
- 2
Pick a language (or let it auto-detect)
Leave it on Auto and it infers JS, TS, JSX or TSX from your code, or force a specific parser with the language control.
- 3
Set your style options
Choose semicolons, single or double quotes, indentation, print width and trailing-comma style. Everything re-runs live as you change options.
- 4
Copy, download or share
Copy the beautified output, download it as a file, or share a link that reopens the tool with your code pre-loaded.
What JavaScript Beautifier includes
Real Prettier, not re-indenting
Code is parsed into a full syntax tree and re-printed by Prettier, so template literals, JSX, decorators, optional chaining and modern ES2022+ syntax all format correctly: where naive beautifiers break.
The options teams argue about
Toggle semicolons, switch single vs double quotes, set 2 / 4 / 8-space or tab indentation, pick a print width for wrapping, and choose trailing-comma style, none, ES5 or all.
Auto-detect language
It reads your snippet and picks JavaScript, TypeScript, JSX or TSX automatically from syntax cues, with a manual override when you want to force a specific parser.
Precise syntax errors
When the input won't parse, the error banner shows the exact line and column Prettier rejected and lets you jump straight to it, instead of a silent, empty output pane.
Live as you type
Formatting runs on every keystroke with a smart debounce and auto-cancels stale runs, so the output stays in sync without a 'Beautify' button dance.
100% in your browser
Prettier runs on your device via a lazy-loaded standalone build. Your source (proprietary logic, embedded keys, client code) is never uploaded, stored or logged.
Why use our javascript beautifier
Turn minified bundles back into readable code
Paste a one-line production bundle or an obfuscated snippet and get properly indented, wrapped, readable code you can actually reason about and debug.
End style debates in code review
Match your team's Prettier config (semicolons, quotes, width, trailing commas) so formatting is consistent and diffs show real logic changes, not whitespace churn.
Format TypeScript and JSX without a toolchain
No local Node install, ESLint config or editor plugin needed: beautify TS and JSX in a browser tab, ideal on a locked-down machine or a colleague's laptop.
Private by design
Because it runs locally, you can safely beautify source that contains secrets, internal API shapes or unreleased features, none of it leaves your machine.
Built for the way you work
From quick one-off fixes to daily workflows, see how people put this tool to use.
- Frontend developer
Unminify a production bundle
Paste a minified vendor or app bundle from your network tab to restore indentation and line breaks, so you can trace a runtime bug back to readable code.
- Full-stack developer
Match a team's Prettier config
Dial in the exact semicolon, quote, width and trailing-comma settings your repo enforces, so pasted snippets land in a consistent, review-ready style.
- Open-source contributor
Clean a snippet before a PR
Beautify a quick fix written in a text box or issue comment before dropping it into the codebase, so it passes CI formatting checks first time.
- Educator / student
Make example code legible
Reformat a cramped one-liner or a dense example into clearly indented code that's easier to read, teach from and understand.
Supported formats
Accepts JS, TS, JSX, TSX and TXT, and produces JS, TS, JSX and TSX, all processed locally in your browser.
- JS
- TS
- JSX
- TSX
- TXT
- JS
- TS
- JSX
- TSX
Frequently asked questions
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Common problems, solved
Hit a snag? Here are quick fixes for the issues people run into most.
It reports a syntax error but the code runs fine.
Prettier needs the code to parse as a complete unit. A stray unbalanced brace, an unterminated string or template literal, or JSX in a file detected as plain JS can all trip it. Try forcing JSX/TSX with the language control, or wrap a bare fragment so it parses.
My TypeScript types were stripped or flagged.
If the language is set to JavaScript, TS-only syntax (type annotations, interfaces, enums) won't parse. Switch the language to TypeScript or TSX, or leave it on Auto so the detector picks the right parser.
Lines aren't wrapping where I expect.
Prettier wraps based on print width, not a hard character cap. It keeps expressions readable rather than truncating mid-token. Lower the print-width value to encourage more wrapping, or raise it to keep more on one line.
Nothing happens on a very large paste.
Extremely large inputs are guarded to keep the tab responsive. Format the file in sections, or trim it first. The limit is generous but not unbounded.
Get the most out of it
Leave the language on Auto. It detects TS and JSX from syntax so you rarely need to choose manually.
Lower the print width (e.g. 60–80) to force more line wrapping, or raise it (100–120) to keep more code on a single line.
Turn semicolons off and quotes to single to match a common StandardJS-style config in one step.
Press Ctrl/Cmd+Enter to re-run instantly, and Ctrl/Cmd+S to download the beautified output.
Set trailing commas to 'all' for cleaner git diffs when adding items to arrays and argument lists.
What's new
Recent updates and improvements to the javascript beautifier.
Initial release, Prettier-powered beautify for JS/TS/JSX/TSX with semicolon, quote, tab-width, print-width and trailing-comma options, live formatting, precise line/column errors, drag-drop import, undo/redo and shareable links.
Added automatic language detection (JS / TS / JSX / TSX) with manual override, plus curated code samples for the empty state.
Refined error messages for unterminated strings and JSX-in-JS mismatches, and added keyboard shortcuts with an in-tool helper.
Keep exploring
Problems we solve
Definitions
From the blog
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Explore categories
Common tasks
Your privacy is built in
Your code is parsed and reformatted entirely in your browser by a lazy-loaded standalone build of Prettier. It is never uploaded to any server. Nothing is stored, logged or transmitted, so you can safely beautify source containing secrets, internal API shapes or unreleased features. Close the tab and every trace is gone.
- Runs in your browser
- No uploads
- Nothing stored
Ready to try the javascript beautifier?
Free, private and instant. JavaScript Beautifier runs right in your browser.