XML Validator
Check whether XML is well-formed and see exactly where it breaks.
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This tool runs entirely on your computer. What you paste or drop is never uploaded, never stored and never seen by us — close the tab and it's gone. How we know
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Worked example
<a><b>1</b></a>✓ Well-formed XMLThis example is one of XML Validator's test cases — if the tool stopped producing this output, the build would fail.
Questions
- Does it validate against an XSD?
- No — it checks well-formedness (tags balanced, entities valid, one root) and reports the exact line and column where it breaks. XSD validation needs your schema and isn't offered here.
- What's the difference between well-formed and valid?
- Well-formed means the XML syntax is correct. Valid means it also conforms to a schema. This tool answers the first question, which is the one that usually bites.