W3C Markup Validation Service

From Wikipedia, the free encyclopedia

The Markup Validation Service by the World Wide Web Consortium, W3C, allows internet users to check HTML documents for conformance to their HTML and XHTML standards. Although HTML files will render regardless of errors in major browsers, they often contain many structure and/or form errors. The Markup Validation Service is not only a good way to make sure documents conform to standards, but is also a quick method to check for errors in code. (Certain other XML documents can also be validated if they refer to an internal or external DTD.)

W3C also offers validation tools for web technologies other than HTML/XHTML, such as MathML.

[edit] External links

• The W3C Markup Validation Service
• W3C QA tools, validation tools for HTML, CSS, RSS/Atom feeds, P3P, XML schemas, etc.
• An "amputator" for excluding errors caused by ad servers from a page's validation results.
• A simple validator with crawling capabilities Web Design Group.