Code Formatter Online
This code formatter online beautifies messy or minified JavaScript, JSON, HTML, CSS, Python, or C/Java with one tap — indenting it properly, breaking it onto readable lines, and leaving it ready to paste back into your editor or a code review. Nothing is uploaded: the whole pass runs inside your browser tab.
How to Format Code Online
- Paste your code into the editor above.
- Leave the language dropdown on Auto-detect, or pick the language yourself if the guess looks wrong.
- Tap Format. Web languages get a full AST-based reformat; Python and C/Java get a structural reindent.
- Tap Copy on the formatted result to grab it for your clipboard.
If the code has a syntax error, Format leaves your original text exactly as you pasted it and shows a warning instead of guessing at broken output.
Supported Languages: JavaScript, JSON, HTML, CSS, Python, C & Java
JavaScript is reformatted with a real parser, so a JavaScript beautifier online pass here handles modern syntax correctly rather than just re-indenting text. The same parser backs JSON formatting, which doubles as a lightweight JSON formatter online validator — code that isn't valid JSON won't format at all, so a clean result means the JSON was valid. HTML gets full HTML tidy online treatment, including embedded scripts and stylesheets, and CSS gets the same CSS beautifier online treatment down to selectors and property blocks. Python and C/Java use a lighter, structural reindent rather than a full parser — enough to fix Python code indentation issues and clean up C-style brace nesting without rewriting the code's logic.
Customizing Indent Style and Size
Every team has its own convention, so this isn't a one-size-fits-all formatter. Open the settings gear next to the language dropdown for code indentation online that matches your project: choose Spaces or Tabs, and with Spaces, pick 2, 4, or 8 per level. The choice applies the next time you tap Format, so you can reformat the same paste with a different style without retyping anything.
Why Formatting Runs in Your Browser
A formatter that sends your code to a server is a formatter that can see your code — a real concern for anything under an NDA, unreleased, or just not yours to share. This tool never makes that trade: parsing and reprinting both happen locally, in a background thread so a large paste doesn't freeze the page, and nothing about the code you paste ever leaves your device.
Frequently Asked Questions
Is this code formatter free to use online?
Yes, this code formatter online is completely free, with no account, no sign-up, and no limit on how many times you format code. There are no ads inside the tool and no watermark on the output — just paste, format, and copy.
Can I switch between spaces and tabs for indentation?
Yes. Open the settings gear next to the language dropdown to choose Spaces or Tabs, and — when Spaces is selected — an indent size of 2, 4, or 8. The next time you tap Format, the output uses whichever style you picked.
Does it validate JSON, or only format it?
Both, as a side effect of how it works. JSON is parsed into a real syntax tree before it's reprinted, so invalid JSON can't be formatted — you'll see the syntax-error warning and your original text stays untouched instead of getting garbled output.
Can it fix Python code indentation automatically?
It can clean up inconsistent indentation — mixed tab widths, uneven spacing between levels — by rescaling every line to your chosen indent size while keeping each line at the same relative depth. It won't rewrite your code's structure or catch logic errors, since Python's indentation is part of the language's meaning and this tool never guesses at that.
Does it tidy messy or minified HTML?
Yes — paste a minified or single-line HTML document and Format breaks it into properly nested, indented markup, including embedded <script> and <style> blocks, which are reformatted too.
Does it support C#, PHP, or SQL?
Not currently. This tool covers JavaScript, JSON, HTML, CSS, Python, and C/Java. C# and other languages aren't supported yet, so pasting them and picking the closest option (like C / Java) may produce an imperfect result rather than a proper reformat.
