Is it valid?   

Valid

Invalid

Please fix me! Featured invalid site

www.history.com

History Channel

417 errors

The History Channel is a cable television station offering programming related to historical events and people.

Categories

Business & Shopping (360), Communities & Blogs (101), Computers (145), Government & Politics (79), Internet (109), News (49), Recreation & Culture (344), Reference (34), Science & Education (98)

Most errors

Hallmark (2751 errors), The Guardian (2280 errors), Continental Airlines (2049 errors), Avril Lavigne (1984 errors), Oh Baby Parenting and Green Living Blog (1740 errors) more... | large chart Chart: sites with the most errors

Notable invalid sites

British Museum (8 errors), National Institutes of Health (64 errors), TripAdvisor (48 errors), Dallas Cowboys (219 errors), Nestle (289 errors) more...

Overall Statistics

Chart: overall statistics

Out of 1511 total sites:

12.7 percent are valid
27.1 percent are slightly invalid (1-20 errors)
28.7 percent are moderately invalid (21-80 errors)
31.5 percent are very invalid (> 80 errors).

The average site has 108 errors.

-- valid8or.com - listing standards compliant sites that use valid W3C HTML/XHTML (and those that don't)