What is well-formed XML?

Well-formed XML adheres to the XML syntax specification: single root element, correctly nested tags, and quoted attribute values.

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XML Validator

Validate XML syntax and detect unmatched tags or well-formedness errors.

How to Use XML Validator

1Paste your XML code into the validator editor.
2Click Validate XML.
3View detailed success status or error message indicating unclosed tags and line numbers.

Key Features & Benefits

DOMParser-powered XML syntax validation
Pinpoints exact error position and mismatched tags
Checks tag nesting and closing balance
100% private in-browser validation

About XML Validator

Check XML documents for well-formedness, missing closing tags, syntax errors, and invalid characters with line and column error indicators.

Unlike traditional web tools that send your personal data, uploaded photos, or sensitive text to remote cloud servers, our XML Validator operates strictly inside your client browser sandbox. This guarantees high processing speeds without network throttling, and ensures your data privacy is completely preserved.