W3C Markup Validation Service

W3C Markup Validation Service

Check the markup validity of web documents with W3C Validator

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Provided by W3C Nu Html Checker
W3C

The World Wide Web Consortium (W3C) is an international organization committed to improving the web. It is made up of several hundred member organizations from a variety of related IT industries. W3C sets standards for the World Wide Web (WWW) to facilitate interoperability and cooperation among all web stakeholders.

It was established in 1994 by the creator of the WWW, Tim Berners-Lee.

Related resources

The W3C Validation Service is a free software created by the W3C to help Web designers and Web developers check document (HTML, XHTML, SMIL etc).
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Learn more about the documentation index and developer resources for W3C Markup Validator.
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