Contents
What does W3C validator do?
The Markup Validator is a free service by W3C that helps check the validity of Web documents. Most Web documents are written using markup languages, such as HTML or XHTML . The Markup Validator can also validate Web documents written with an SGML or XML DTD , provided they use a proper document type declaration.
What does count as an error for the HTML5 validator?
So, you ask, what does count as an error for the HTML5 validator? It will alert you to the incorrect use of elements, elements included where they shouldn’t be, missing required attributes, incorrect attribute values, and the like.
What are some types of errors that a validation will not help you find?
Why validate?
Why is it important to use the W3C Markup Validation Service?
The Markup Validation Service is a validator by the World Wide Web Consortium (W3C) that allows Internet users to check pre-HTML5 HTML and XHTML documents for well-formed markup against a document type definition. Markup validation is an important step towards ensuring the technical quality of web pages.
Why is my W3C markup validation service not working?
This is often caused by a leftover end tag from an element that was removed during editing, or by an implicitly closed element (if you have an error related to an element being used where it is not allowed, this is almost certainly the case). In the latter case this error will disappear as soon as you fix the original problem.
Why do I get an error message from the validator?
Below are all the validator’s error messages for which we have an “explanation”. This is usually a cascading error caused by a an undefined entity reference or use of an unencoded ampersand (&) in an URL or body text. See the previous message for further details.
Why is the parent element not finished W3C?
Another possibility is that you used an element which requires a child element that you did not include. Hence the parent element is “not finished”, not complete.