What generally happens when you click on a 'Valid XHTML' link that a developer has put at the bottom of a web page—to proudly proclaim their adherence to web standards—is that the validator tells you the page isn't valid at all and has approximately 197 errors. Here's a test of the first 100 results of a Google search for sites that link to http://validator.w3.org/check/referer (and bear in mind that these are sites with a reasonable PageRank, so have perhaps spent more time on their coding than those lower down in the results):
http://plone.org/products/plonemultimedia/releases/1.0-alpha1 | XHTML 1.0 Transitional |
Failed validation, 1 error | |
http://xmlns.com/foaf/0.1/ | XHTML 1.0 Strict |
Failed validation, 397 errors | |
http://valet.webthing.com/page/format.html | HTML 4.01 Strict |
Valid | |
http://www.usu.edu/alumnifriends/ | XHTML 1.0 Transitional |
Valid | |
http://happycog.com/pubs/ | XHTML 1.0 Strict |
Valid | |
http://www.hwg.org/services/classes/phptraining.html | XHTML 1.0 Transitional |
Failed validation, 1 error | |
http://www.royalsoc.ac.uk/landing.asp?id=7 | XHTML 1.0 Transitional |
Valid | |
https://www.fsf.org/about/contact.html | XHTML 1.0 Transitional |
Failed validation, 7 errors | |
http://www-sop.inria.fr/act_recherche/formation/stages_theses_fr.shtml | HTML 4.01 Transitional |
Valid | |
http://www.ercim.org/publication/Ercim_News/enw63/lalmas.html | HTML 4.01 Transitional |
Failed validation, 2 errors | |
http://google.blognewschannel.com/ | XHTML 1.0 Transitional |
Failed validation, 243 errors | |
http://nave.escomposlinux.org/glosario/ | HTML 4.01 Transitional |
Valid | |
http://www.starling-fitness.com/ | XHTML 1.0 Transitional |
Valid | |
http://www.gnupg.org/misc/links.html.en | XHTML 1.0 Strict |
Valid | |
http://www.unr.edu/content/outreach.asp | XHTML 1.0 Transitional |
Valid | |
http://plone.org/news/newslisting/folder_summary_view?b_start:int=480 | XHTML 1.0 Transitional |
Failed validation, 1 error | |
http://www.cs.utexas.edu/~AustinVilla/ | XHTML 1.0 Strict |
Failed validation, 4 errors | |
http://www.addfaq.com/?cat=2 | XHTML 1.0 Transitional |
Failed validation, 265 errors | |
http://web.mit.edu/sailing/www/SailingTeam/ | XHTML 1.0 Strict |
Failed validation, 12 errors | |
http://www.newsoftwaretitles.com/?p=76 | XHTML 1.0 Transitional |
Failed validation, 201 errors | |
http://microformats.org/blog/2006/01/10/publishing-events-with-wordpress-20/ | XHTML 1.0 Strict |
Valid | |
http://plone.org/products/lbluegray-plone-skin/releases/1.3 | XHTML 1.0 Transitional |
Failed validation, 1 error | |
http://plone.org/events/sprints/padova | XHTML 1.0 Transitional |
Failed validation, 5 errors | |
http://datacentral.sdsc.edu/user_guide.html | XHTML 1.0 Transitional |
Failed validation, 2 errors | |
http://www.uiaccess.com/scaletext.html | (no Doctype found) |
Failed validation, 1 error | |
http://www.psigate.ac.uk/newsite/ | (no Doctype found) |
Failed validation, 2 errors | |
http://www.imag.fr/ | XHTML 1.0 Strict |
Failed validation, 2 errors | |
http://ieas.berkeley.edu/gas/undergrad_program.html | XHTML 1.1 |
Valid | |
http://www.ercim.org/publication/Ercim_News/enw51/berners-lee.html | HTML 4.01 Transitional |
Failed validation, 2 errors | |
http://coppermine-gallery.net/forum/ | XHTML 1.0 Transitional |
Valid | |
http://www.mezzoblue.com/articles/ | XHTML 1.0 Strict |
Valid | |
http://www.ictp.it/pages/mission/support.html | XHTML 1.0 Transitional |
Valid | |
http://impressive.net/people/gerald/2001/ | HTML 4.0 Transitional |
Valid | |
http://www.ndsu.nodak.edu/graduate/ | XHTML 1.0 Transitional |
Valid | |
http://www.w3c.es/Consorcio/contacto | XHTML 1.0 Transitional |
Valid | |
http://www.entemp.ie/ | HTML 4.01 Transitional |
Valid | |
http://www.cgeu.org/ | XHTML 1.0 Strict |
Failed validation, 1 error | |
http://etext.library.adelaide.edu.au/ | HTML 4.01 Strict |
Failed validation, 7 errors | |
http://lugww.counter.li.org/ | HTML 4.01 Transitional |
Valid | |
http://trizpug.org/gallery/pbc2005/pbc_group_3.jpg/view | XHTML 1.0 Transitional |
Failed validation, 3 errors | |
http://ieas.berkeley.edu/cks/courses.html | XHTML 1.1 |
Valid | |
http://www.afb.org/blog/ | HTML 4.01 Transitional |
Valid | |
http://vlib.org/Recreation.zh | XHTML 1.0 Transitional |
Valid | |
http://vlib.org/Religion.fr | XHTML 1.0 Transitional |
Valid | |
http://www.arch.cam.ac.uk/server/about.html | XHTML 1.0 Transitional |
Valid | |
http://www.w3schools.com/tags/default.asp | XHTML 1.0 Transitional |
Valid | |
http://www.cpsr-peru.org/Blog/iim2/view?searchterm=electronic%20frontier | |
Valid | |
http://www.asu.edu/aad/catalogs/ | XHTML 1.0 Transitional |
Valid | |
http://www.ams.org/mathweb/mi-reference.html | HTML 4.01 Transitional |
Failed validation, 1 error | |
http://www.ximinc.com/corporate/privacy.php | HTML 4.01 Transitional |
Valid | |
http://www.plonesolutions.com/contact | XHTML 1.0 Transitional |
Valid | |
http://www.w3c.es/Politica/PoliticaOficina | XHTML 1.1 |
Valid | |
http://www.ams.org/mathweb/mi-journals.html | HTML 4.01 Transitional |
Valid | |
http://osflash.org/tutorials | XHTML 1.0 Transitional |
Valid | |
http://www.usweb.com/online_marketing_firm/press_kit/company_overview.htm | XHTML 1.0 Strict |
Valid | |
http://www.hwg.org/lists/hwg-style/ | HTML 4.0 Transitional |
Valid | |
http://www.v-2.org/ | XHTML 1.0 Transitional |
Valid | |
http://plone.org/author/munwar | XHTML 1.0 Transitional |
Failed validation, 1 error | |
http://www.culturedcode.com/xyle/features.html | XHTML 1.0 Strict |
Valid | |
http://www.dopefly.com/ | XHTML 1.0 Strict |
Valid | |
http://www.webmilhouse.com/ | (no Doctype found) |
Failed validation, 3 errors | |
http://x.cygwin.com/docs/ug/ | XHTML 1.0 Transitional |
Valid | |
http://www.odeyssa.com/ | XHTML 1.0 Strict |
Valid | |
http://www.maut.mcgill.ca/ | XHTML 1.0 Transitional |
Failed validation, 1 error | |
http://www.tacoma.washington.edu/ias/admissions/ | XHTML 1.0 Transitional |
Failed validation, 1 error | |
http://www.cknudsen.com/javacaltools.php?topic=Download | XHTML 1.0 Transitional |
Valid | |
http://led.loria.fr/pratique.html | HTML 4.01 Transitional |
Valid | |
http://plone.org/events/regional/nola06 | XHTML 1.0 Transitional |
Failed validation, 27 errors | |
http://www.wmich.edu/ | XHTML 1.0 Transitional |
Failed validation, 8 errors | |
http://www.chemweb.com/alchemist-current | XHTML 1.0 Transitional |
Failed validation, 66 errors | |
http://www.monkeymind.net/portfolio.html | XHTML 1.0 Transitional |
Valid | |
http://www.headlineviewer.com/skins.shtml | HTML 4.01 Transitional |
Valid | |
http://www.21coe.keio.ac.jp/ | HTML 4.01 Transitional |
Failed validation, 4 errors | |
http://plone.org/events/sprints/paderborn | XHTML 1.0 Transitional |
Failed validation, 1 error | |
http://plone.org/development/teams/optimization | |
Valid | |
http://plugindoc.mozdev.org/sitemap.html | HTML 4.01 Strict |
Valid | |
http://wiki.splitbrain.org/wiki:press | XHTML 1.0 Transitional |
Valid | |
http://www.daisy.org/projects/default.asp | XHTML 1.0 Transitional |
Valid | |
http://www.addfaq.com/?cat=8 | XHTML 1.0 Transitional |
Failed validation, 249 errors | |
http://wonderweb.semanticweb.org/participants.shtml | XHTML 1.0 Transitional |
Valid | |
http://wonderweb.semanticweb.org/participants.shtml | XHTML 1.0 Transitional |
Valid | |
http://www.fsf.org/licensing/index_html/SimpleBlogFullSearch | XHTML 1.0 Transitional |
Valid | |
http://dublincore.org/groups/coverage/ | XHTML 1.0 Transitional |
Valid | |
http://www.artypapers.com/ | XHTML 1.0 Transitional |
Valid | |
http://www.michaelcrow.net/ | XHTML 1.0 Transitional |
Failed validation, 12 errors | |
http://en.magenson.de/2006/03/ | XHTML 1.0 Transitional |
Failed validation, 3 errors | |
http://plone.org/products/faqulator/releases/1.3 | XHTML 1.0 Transitional |
Failed validation, 1 error | |
http://www.mainewebreport.com/ | XHTML 1.0 Transitional |
Failed validation, 22 errors | |
http://osflash.org/aswing | XHTML 1.0 Transitional |
Valid | |
http://www.kryogenix.org/days/2003/12/ | XHTML 1.0 Transitional |
Failed validation, 2 errors | |
http://www.gnome.org/contact/ | XHTML 1.0 Transitional |
Valid | |
http://www.fsf.org/blogs/rms/entry-20060125.html | XHTML 1.0 Transitional |
Failed validation, 40 errors | |
http://www.w3c.de/news.html | XHTML 1.0 Strict |
Valid | |
http://www.w3c.se/nl-news/nl-2003-03-06.html | HTML 4.0 Transitional |
Valid | |
http://www.hwg.org/services/classes/photoshoptraining.html | XHTML 1.0 Transitional |
Failed validation, 13 errors | |
http://www.hwg.org/services/classes/asptrainingcourse.html | XHTML 1.0 Transitional |
Failed validation, 1 error | |
http://plone.org/events/sprints/berne | |
Valid | |
http://www.ercim.org/publication/Ercim_News/enw63/guelfi.html | HTML 4.01 Transitional |
Failed validation, 2 errors | |
http://www.ercim.org/publication/Ercim_News/enw63/ricca.html | HTML 4.01 Transitional |
Failed validation, 2 errors | |
http://www.ee.surrey.ac.uk/Research/VSSP/VideoAnnotation/tennis/ | XHTML 1.0 Strict |
Failed validation, 10 errors |
URL/Doctype/Claim/Result of validation