Developer tool
XML Formatter & Validator
Paste XML, then format it with proper indentation or check whether it's well-formed.
"Well-formed" vs "valid"
This tool checks that your XML is well-formed — every tag properly opened and closed, correctly nested — which is what a browser's XML parser requires. It doesn't check against a schema (DTD or XSD), so well-formed XML can still fail a stricter validation elsewhere.