JSF
JS Formatter
Tidy JavaScript with basic indentation.
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How to use JS Formatter
Tidy JavaScript with basic indentation.
- Paste compact JavaScript into the Your text field.
- Press Run to put braces and statements on their own lines.
- Copy the readable code back into your project.
Practical note. The formatter understands modern JavaScript syntax, including arrow functions, template literals and optional chaining, so it will not mangle ES6+ code.
When you actually reach for this
- You pasted minified or messy JavaScript and need to step through it, so you want consistent indentation and brace style.
- A teammate committed inconsistently formatted code and you want a canonical layout before review.
Where this tool stops being accurate
- Automatic formatting can change line numbers in source maps, so re-generate maps after formatting if you debug minified builds.
- A formatter will not fix logic errors or ambiguous Automatic Semicolon Insertion traps; it only lays out valid syntax.
Frequently asked questions
What does JS Formatter do?
Tidy JavaScript with basic indentation.
Can pretty-printing a minified bundle reveal what it does?
It restores readability (names stay mangled, but structure returns), which helps audits — but for true understanding you still need to trace the logic, not just indent it.
Will formatting change my code behavior?
Not for valid JS. The only risk is ASI edge cases where missing semicolons already made parsing fragile; a good formatter preserves the parsed meaning.