justyourdevJavaScript Formatter
Beautify JavaScript with Prettier, right in your browser.
- 100% Free
- No Sign Up
- Works in Your Browser
JavaScript formatter
Beautify JavaScript code
Indent
Quotes
Everything runs in your browser. Nothing is uploaded.
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Every everyday developer tool, right in your browser.
No installs. No uploads. No signup.
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How to use the JavaScript formatter
Three steps, all in your browser.
- 1
Paste your input
Type or paste your code or data. Press Sample to try an example.
- 2
Pick the style
Choose indentation or options. The result updates as you type.
- 3
Copy the result
Copy the output in one click. Nothing is saved or sent anywhere.
JavaScript Formatter: what to know
The JavaScript formatter runs Prettier in your browser to rewrite code with consistent indentation, line breaks, quotes and semicolons. It understands modern JavaScript, including modules, classes, async/await, optional chaining and JSX, can switch to TypeScript (TSX), and reports a syntax error with its location if the code can't be parsed.
It's also a quick way to make minified code readable. Indentation and line breaks come back, so you can follow the control flow, but anything the minifier threw away stays gone: short variable names like a and b aren't restored and comments don't reappear. For that you need the original source or its source map.
Prettier is opinionated on purpose. Instead of dozens of style options it applies one consistent style, which is why many teams run it on every save. Running it here with the default options gives the same result as Prettier's defaults in your editor.
Popular uses
- Reading minified scripts from a website or package
- Tidying snippets before sharing them in a pull request or issue
- Formatting code copied from a chat, email or PDF
- Checking code for syntax errors quickly
Tips for the best result
- If code from a PDF or chat won't parse, look for smart quotes or non-breaking spaces that came along with it.
- Type annotations only parse in TypeScript mode; switch the language if you see an error at a colon or angle bracket.
- Use the JavaScript minifier for the opposite direction.
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