HTML vs XHTML version statistics

As part of the online demo at try.powermapper.com we collect summary statistics about pages scanned by our service. One interesting statistic covers versions of HTML and XHTML in common use. As of March 2019:

• HTML 5 DOCTYPEs account for over 90% of pages scanned (up from 8% in 2011)
• XHTML 1.0 DOCTYPEs account for under 5% of pages scanned (down from 60% in 2011)
• XHTML 1.1 DOCTYPEs have vanished, and account for 0% of pages scanned (down from 1% in 2011)
• HTML 4.01 DOCTYPEs account for about 1% of pages scanned (down from 10% in 2011)
• About 2% of pages scanned have no DOCTYPE (down from 5% in 2011)

HTML vs. XHTML Version Statistics

This is based on a sample size of over 20 million pages on 2 million web sites.

Note: the graph in this post is live, so may show newer data than the date of this post.