Q: What is the difference between well-formed and valid XML?

Well-formed XML follows basic XML syntax rules (properly nested tags, quoted attributes, one root). Valid XML additionally conforms to a specific schema (DTD or XSD) that defines which elements and attributes are allowed. The validator checks well-formedness; schema validation requires a separate schema file.

Q: Is my XML data safe here?

Yes. Processing runs in your browser. Nothing is sent to a server.

Question 1

What is XPath and how do I use it?

Accepted Answer

XPath (XML Path Language) is a query language for selecting nodes in an XML document. Basic examples: /root/child selects all elements inside ; //item selects all elements anywhere in the document; /books/book[@category='fiction'] selects books with a category attribute equal to 'fiction'. Enter an XPath expression in the query field and the matching nodes are highlighted and listed.

Question 2

What makes XML invalid?

Accepted Answer

Common causes: missing closing tags, mismatched tag names (case-sensitive: ≠ ), unclosed attribute quotes, & not encoded as &, < not encoded as < in text content, multiple root elements (XML requires exactly one), and invalid characters in element names.

Question 3

What is the difference between well-formed and valid XML?

Accepted Answer

Well-formed XML follows basic XML syntax rules (properly nested tags, quoted attributes, one root). Valid XML additionally conforms to a specific schema (DTD or XSD) that defines which elements and attributes are allowed. The validator checks well-formedness; schema validation requires a separate schema file.

Question 4

Is my XML data safe here?

Accepted Answer

Yes. Processing runs in your browser. Nothing is sent to a server.

XML Tools Suite

XML tools — format, validate, transform

XML Tools Suite

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XML tools — format, validate, transform