News for the W3C Markup Validator

This page lists recent changes to the W3C Markup Validation Service. For minor changes and bug fixes that aren't listed on this page, see the CVS log.

2004-07-23 — 0.6.7 Release:

A maintenance release that fixes a few minor bugs, improves authentication proxying, and makes some slight tweaks to the website style and markup.

This version also more completely fixes the bug mentioned at the end of the previous version's release notes. See the v0.6.6 release notes for details.

2004-05-21 — 0.6.6 Release:

A maintenance release that fixes a few minor bugs, resurrects the whitespace-preserving source display, adds explanations for additional error messages, and makes some slight tweaks to the website style.

This version also tentatively fixes a bug where, for Document Instances with a Document Type Name of "html", but with an incorrect Formal Public Identifier, the Validator would fall back to HTML 4.01 Transitional and, if no other errors were found, silently ignore the erroneous FPI.

2004-05-07 — 0.6.5 Release:

Stable release including all the fixes and improvements made in consecutive beta versions 0.6.5 Beta #3, 0.6.5 Beta #2, 0.6.5 Beta #1, 0.6.2 beta #2, and 0.6.2 beta #1

2004-04-30 — 0.6.5 Beta #3:

Testing version 0.6.5 Beta #3 of the Markup Validator; an intermediary version including further layout, style and documentation improvements over version 0.6.5 Beta #2, based on discussion and comments during the testing phase of that version. Changes include:

  • Simpler navigation system - removed the "links" navigation bar
  • More consistent layout
  • A few issues with the way some agents were dealing with our Style Sheets were fixed. Other minor style fixes were also applied.
  • Cleanup of grammar issues and typos in a large part of the documentation.
2004-04-15 — 0.6.5 Beta #2:

Testing version 0.6.5 Beta #2 of the Markup Validator; an intermediary version addressing comments received for the version 0.6.5 Beta #1 and adding significant User Interface and Documentation improvements. Changes include:

  • More explanations for most of the validation error messages
  • New documentation on installing the Markup Validator locally
  • The "fussy" parsing mode is no longer available and will be drastically improved before it comes back - if ever
  • The W3C Link Checker has now been spun off into a standalone product and is no longer bundled with the Markup Validator
  • Stylesheets have been updated, with a more pleasant look
  • Easier navigation, more accessible documentation
  • More "Quality Tips" have been added
2003-08-26 — 0.6.5 Beta #1:

Testing version 0.6.5 Beta #1 of the Markup Validator; an intermediary version addressing various issues and add requested features. Changes include:

  • Stylesheets updated to work around browser issues.
  • Added a pointer to contributed RPMs courtesy of Ville Skyttä.
  • Fixed broken links in Copyright statement.
  • Added current version number in page headings.
  • Detect proxies stripping the Referer header.
  • Added "Comma Tools".
  • Minor Accessibility fixes.
  • A few new Webmaster Tips for the Tip of The Day.
  • The Link Checker now sends Accept, and Accept-Language headers.
  • The Link Checker supports more HTTP Status Codes.
  • The documentation has seen much improvement.
  • The RPM spec file is now available in the download.
  • Update ISO-HTML DTD to TC1.
  • Update SVG 1.0 DTD to current Errata.
  • Added support for ISO-8859-16 Encoding.
  • Added support for the data: URL scheme.
  • The Link Checker in command-line mode now supports bundling of options.
  • The Validator RPMs now try to integrate with the system catalog.
  • Added options to make the DOCTYPE and Charset Override behave like Fallbacks. i.e. With these options enabled, the Override will only insert the relevant new value iff one was not already present.
  • No longer treat missing DOCTYPE or Charset as a fatal error.
  • Much improved error messages for several error situations.
  • Updated and expanded error explanations.
  • Use passive (PASV) FTP by default.
  • Updated experimental mod_perl support to work with Apache/mod_perl 2.
  • Added support for the Big5-HKSCS encoding.
  • The MathML2 DTDs were updated to the 20030620 errata version.
  • Add option to restrict access to private IP addresses.
  • Added custom, inline, verbose error messages.
  • Tweaked markup and style for source display.
  • Tweaked markup and style for indicating position of error.
  • Changes in output mandated by W3C Legal.
  • Verbose output is now the default from the home page.
  • Added new "fussy" parse mode (enabled by default from the home page) that should make it easier to locate SHORTTAGS-related problems (such as implied end tags).
  • Valid Badge usage guidelines are now available.
  • Various internal restructuring to make way for future (post-0.6.5) features.
  • "/referer" is now deprecated in favor of "?uri=referer"; this allows us to preserve additional options in referer links.
2002-12-01 — 0.6.1 Release:
  • Maintenance release to fix various minor issues reported against the November 26 release. Stylesheet updates, ability to turn on Verbose output, and bug fixes.
2002-11-26 — 0.6.0 Release:
  • Improved design of layout, including for Validation results.
  • Added "beefed up" Tip-of-the-Day.
  • Many accessibility fixes, both to the web site and the Result page.
  • Major internal restructuring. The code has undergone significant refactoring with many benefits. It is more readable and easier to understand, much more robust, much improved security, more modular, and performance should be significantly better. There is tentative support for running under mod_perl (leading to even greater performance enhancements) and memory consumption should be much improved.
  • Many new document types are supported and support for some existing document types has been improved. Notable changes and additions include:
    • Support for application/xhtml+xml.
    • Support for XHTML+MathML and XHTML+MathML+SVG.
    • Support for SVG and image/svg+xml.
    • XHTML 1.0 Second Edition and XHTML 1.1.
  • Output has been reworked to be easier to understand.
  • And a whole bunch of bugfixes... :-)
  • Finished redesign and use consistent style for all pages..
  • Added Tip-of-the-Day.
  • Added experimental support for SVG 1.0.
  • Added experimental support for spec-prod 2.0.
  • ...and several minor bug fixes.
  • Added support for XHTML 1.1 and XHTML Basic 1.0.
  • Added experimental support for MathML 2.0.
  • You can now tweak options from results page.
  • Added option to override Character Encoding.
  • Various bug fixes and minor changes.
  • Various bug fixes; notably two related to the File Upload feature.
  • Some changes to make local installations easier.
  • Support for more Character Encodings (e.g. ISO-8859-8-I).
  • Generally improved handling of Character Encodings.
  • Documentation donated by Scott Bigham (Thanks Scott!).

Added support for ISO/IEC 15445:2000 (ISO-HTML). See also: User's Guide to ISO-HTML.


The service now checks XHTML documents for validity as well as XML well-formedness.


Added the file upload feature.

Created the www-validator-cvs mailing list.

Updated the home page, moved some things to another page.


Updated the DTDs and added icons for XHTML 1.0, HTML 4.01.


Added the DTDs for HTML 4.01.

Updated the DTDs for XHTML 1.0.


Added username/password proxying for validation of documents protected by HTTP Basic Authentication, thanks to patches from Renaud Bruyeron. (see the changes)

This revision also includes patches to use the Perl5 version of libwww-perl, LWP.


Added support for XHTML, using the DTDs from the 19990304 working draft. (see the changes)


Added support for ISO-2022-JP and Shift_JIS character encodings. Thanks to Takuya Asada, Masayasu Ishikawa, and Martin Dürst for their patches and advice.

Updated the SGML declaration according to the HTML 4.0 spec errata. (see the changes).


Put a tarred and gzipped version of the SGML library files (DTDs etc.) on the Web.


Posted some new documents on the Web:


Made the source code available via W3C's public CVS tree.

Upgraded the HTTP server to Apache 1.3.1.


Added a page about the hardware/network behind this service.


Added support for a parameter to check the referring Web page for mistakes. To use it, just link to the following URL when linking to the service <> (you can try the link to see how it works).


Updated HTML 4.0 materials to match the HTML 4.0 Recommendation.

Valid XHTML 1.0!Feedback: Das Valid-Html.Info Validator Team