Does this validate against a schema (XSD)?

No — it checks that the XML is well-formed (properly nested and closed tags), not that it conforms to a specific schema.

What happens with malformed XML?

The tool reports that the document isn't well-formed rather than guessing at a fix.

Format and validate XML code.

<note><to>Ada</to><from>Bob</from><message>Hello there</message></note>

Your file never leaves this browser tab — everything runs locally on your device.

Making minified or single-line XML (like an API response or config file) readable.
Checking whether an XML document is well-formed before using it elsewhere.
Cleaning up XML for documentation or a code review.

Compare two JSON documents side by side and see exactly what changed.

Create a downloadable QR code from any text or URL.

Decode a JWT's header and payload. Decoding is not signature verification.

Generate one or many random UUID v4 values.