Does this catch mismatched tags?

Yes. Your XML is checked for well-formedness with the browser's native XML parser before formatting — a mismatched closing tag or other structural problem is reported as an error rather than silently fixed.

Are comments and CDATA sections preserved?

Yes, both are kept as-is in the formatted output.

Code Formatters

XML Formatter

Format XML into readable, indented markup. Well-formedness is checked with the browser's native XML parser first, so a genuinely malformed document (like a mismatched closing tag) is reported as an error instead of being silently repaired.

Indentation

XML

Formatted XML

JSON Formatter

Pretty-print and validate JSON with configurable indentation.

HTML Formatter

Beautify HTML, including embedded CSS and JavaScript.

Features

Real well-formedness validation, not just indentation
Preserves comments, CDATA sections, attributes, and declarations
2, 4-space, or tab indentation

How to use

Paste your XML into the input.
Pick an indentation size and click Format.
If the XML isn't well-formed, the error explains what's wrong.

Example

Input

<root><a>1</a><b>2</b></root>

Output

<root>
  <a>1</a>
  <b>2</b>
</root>

FAQ

Does this catch mismatched tags?: Yes. Your XML is checked for well-formedness with the browser's native XML parser before formatting — a mismatched closing tag or other structural problem is reported as an error rather than silently fixed.
Are comments and CDATA sections preserved?: Yes, both are kept as-is in the formatted output.