W3C Offline HTML Validator A Visual Studio Code extension that provides offline HTML validation using W3C standards. This extension integrates the W3C Nu HTML Checker directly into VSCode, allowing ...

W3C Offline HTML Validator A Visual Studio Code extension that provides offline HTML validation using W3C standards. This extension integrates the W3C Nu HTML Checker directly into VSCode, allowing ...

The MarkUp Validation Service checks for compliance with different HTML versions and the emerging XHTML standard—an evolutionary change to HTML markup that's XML-compliant.

The MarkUp Validation Service checks for compliance with different HTML versions and the emerging XHTML standard—an evolutionary change to HTML markup that's XML-compliant.

Just ask the Unicorn. The web's governing body has launched a new validation tool called Unicorn that checks the quality of your website's code against multiple web standards at once.

“HTML started simply, with structured markup, no licensing requirements, and the ability to link to anything,” said Tim Berners-Lee, W3C director and inventor of HTML, in a statement.

Google’s John Mueller recently stated in a webmaster hangout that W3C validation has no impact on search results.

Le Hégaret noted in a W3C blog post on Tuesday that the HTML Working Group is finding failures in just 3.3 percent of its 97,000 HTML5 tests.