HTML Validation Service: About

About the W3C HTML Validation Service

This service checks HTML documents for conformance to W3C HTML and XHTML Recommendations and other HTML standards. Related resources include:

• Source code availability.
• The to-do list for the service.
• DTDs (document types) supported by this service (the SGML catalog).
• The www-validator mailing list.
• How to provide feedback.

Other resources

• W3C's HTML home page.
• The W3C HTML 4.01 Recommendation
• The W3C XHTML 1.0 Recommendation
• The WDG HTML validator is another excellent online validation service
• A Real Validator is a shareware HTML syntax checker for Windows systems, from the author of the WDG validator
• Clean up your HTML using HTML tidy
• Site Valet by Nick Kew is a comprehensive set of tools that will cover all needs from the personal home page to corporate web sites.

Credits

• James Clark's excellent SGML parser.
• The LWP Perl Modules by Gisle Aas and Martijn Koster for retrieving documents.
• SGML error explanations written by Scott Bigham.
• Patches and ideas from:
  • Terje Bless
  • Liam Quinn