Check whether an XML string is well-formed — catches mismatched tags, missing closing elements, and structural errors.
Frequently asked questions
It means the basic syntax rules are followed — every tag is properly closed and nested, attributes are quoted, and there's exactly one root element. It's different from "valid against a schema" (like a DTD or XSD), which this tool doesn't check.
Unclosed tags, mismatched opening/closing tags, invalid characters, and multiple root elements are the most common issues it will catch.