XML Validator
Check XML for well-formedness and report every error with its line and column number.
How it works
- 1
Paste the XML you want to check into the input area.
- 2
Press Validate XML — the tool inspects every tag, attribute, and nesting rule.
- 3
Read the result: a green confirmation for valid XML, or an error pinpointing the exact line and column.
Questions
What exactly is checked?
Well-formedness: every opening tag must have a matching close, attributes must be quoted, and the document must have a single root element.
Does this validate against a schema or DTD?
No — it checks structural well-formedness only. Schema (XSD) or DTD validation is not performed.
Is my XML uploaded?
No. Validation runs on-device in your browser. Your content stays on your machine.
Why does it show a line number?
The parser tracks its position as it reads the document, so when it hits an error it can tell you exactly where to look.
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