Check HTML online
Run Current Document (W3C) to send the active HTML source to the online validator. This check needs an internet connection.
Check the active document, review the results and return to the source to correct markup issues before publishing.
Run Current Document (W3C) to send the active HTML source to the online validator. This check needs an internet connection.
Read the reported errors, warnings and other messages while the document is open.
Select a result with a location to reveal the relevant line in the editor. Correct the markup and run the check again.
Use As XML for a local well-formedness check. This checks XML syntax rather than HTML conformance.