FREE WEB TOOL

Find XML Syntax Errors and Format XML

Locate XML syntax errors and format valid XML with readable indentation.

Use tool

How to use it

Format XML with readable line breaks and indentation while checking whether the input is basically well-formed XML. It is useful for inspecting compact configuration files, feeds or API responses.

  1. Paste the XML into the input field.
  2. Select Format.
  3. Review the indented result, or fix tags and attributes if a syntax error is reported.
Syntax errors
Catches problems such as broken closing tags or malformed attributes
Output
Readable line breaks and indentation
Validation scope
Basic XML well-formedness
Not included
Business-rule or XSD validation

Turn one-line XML into a visible element hierarchy

<root><item id="1">A</item></root> becomes a multi-line view where the root/item nesting is easier to inspect.

Well-formed XML is not automatically valid for a particular service. Required elements, allowed values, XSD rules and application-specific constraints are outside this formatter’s validation scope.

Malformed tags are stopped before formatting

Missing closing tags, broken attribute quotes and similar XML syntax problems produce an error instead of a misleading pretty-printed result.

Indentation makes nesting easier to inspect

When XML contains several levels of elements, a formatted copy makes parent-child relationships easier to review during debugging or manual checks.

Application rules need separate validation

An XML document can be perfectly well-formed and still violate a feed, API or schema requirement. Use the destination specification or XSD when those rules matter.

Whitespace-sensitive mixed content deserves care

XML that mixes running text with child elements can treat whitespace as meaningful data. Check the formatted output before using it where those spaces or line breaks matter.

Keep the original when the document is important

Use the formatted version as a review copy rather than overwriting the only source file, especially when you are diagnosing a production configuration or data feed.

Related references: HTTP status codes · MIME types · Regex cheat sheet