Developer Tools
HTML Formatter Online
Beautify HTML markup with readable indentation for debugging, review and maintenance. Processing happens locally in your browser.
About HTML Formatter
HTML Formatter turns compact or inconsistently indented markup into a readable structure for debugging, code review and maintenance. It is useful for web pages, templates, email markup and generated HTML. Formatting changes whitespace and indentation only; it does not guarantee that the document is valid, accessible or semantically correct.
Key Features
How to Use
- Paste the HTML markup into the input editor.
- Select the format action and review the indented output.
- Check that script, style, pre and template content still behaves as expected.
- Copy the formatted version into your editor or code-review workflow.
Practical Example
Input
<main><h1>Report</h1><section><p>Ready</p></section></main>
Output
<main>
<h1>Report</h1>
<section>
<p>Ready</p>
</section>
</main>Popular Use Cases
Best Practices
- ✓ Validate important documents after formatting.
- ✓ Keep semantic elements and accessibility attributes intact.
- ✓ Test whitespace-sensitive content such as preformatted text.
- ✓ Use an HTML linter or browser validator for structural issues.
Common Mistakes
- • Assuming formatting repairs invalid or unclosed markup.
- • Replacing the original file without reviewing the result.
- • Ignoring whitespace-sensitive inline or preformatted content.
- • Treating attractive indentation as proof of accessibility.
Privacy and Processing
HTML entered into this formatter is processed locally in your browser during normal use. The tool does not need to upload page markup to a formatting service.
Important limitation: The formatter improves readability but does not execute templates, resolve framework syntax, validate accessibility or guarantee browser compatibility.
Frequently Asked Questions
Does formatting change how HTML works?
It is intended to change indentation and whitespace only, but whitespace-sensitive content should always be tested.
Can it repair invalid HTML?
No. Use an HTML validator or browser developer tools to diagnose structural errors.
Can I format an HTML fragment?
Yes. Full documents and smaller fragments can both be formatted.
Is it suitable for email HTML?
It can improve readability, but test the final email in the clients you support because email rendering rules vary.
Can formatted HTML be minified again?
Yes. Use the HTML Minifier when you need a compact production copy.
Is my markup stored?
No. Normal formatting occurs locally in the browser.