XML Validator
Check whether a document is well-formed XML.
This XML Validator checks whether a document is well-formed XML — correctly nested and closed tags, valid structure — without checking it against any specific schema. Paste or upload XML and click Validate; if it isn't well-formed, the line and column of the problem are shown when available. Nothing leaves your browser.
How to use
- 1Paste XML into the input, or upload an .xml file.
- 2Click Validate.
- 3If the XML isn't well-formed, the line and column of the problem are shown when available.
Frequently asked questions
What does "well-formed XML" mean?
It means the document follows XML's basic syntax rules — every tag is properly opened and closed, elements are correctly nested, and there's exactly one root element. It's a lower bar than being valid against a specific schema or DTD.
Does this validate against a schema (XSD/DTD)?
No — it only checks well-formedness (correct tag structure), not conformance to a particular schema. If you need schema validation, this tool won't cover that.
Why check this before using an XML file?
A single unclosed or mismatched tag will make most XML parsers throw an error with a confusing stack trace. Catching it here first, with the exact line and column, is quicker to fix.
Is my document uploaded anywhere?
No. Validation runs entirely in your browser using the native parser — nothing leaves your device.