HTML5 DocType
23,643,684 websites

HTML5 DocType is free to use

http://www.w3.org/html/wg/drafts/html/master/syntax.html#the-doctype

The DOCTYPE is a required preamble for HTML5 websites.

VS

Meta Keywords
7,523,563 websites

Meta Keywords is free to use

http://www.wordstream.com/meta-keyword

Meta Keywords are a specific type of meta tag that appear in the HTML code of a Web page and help tell search engines what the topic of the page is.

Market Share by Top Websites

1 HTML5 DocType is leading in Top 10K Sites, Top 100K Sites, Top 1M Sites and The Entire Web.

2 In terms of market share, Meta Keywords is clearly lagging behind, losing to HTML5 DocType in all segments.

Websites Categories

1 HTML5 DocType has better usage coverage in more websites categories. Including Computers Electronics & Technology, Science & Education, Arts & Entertainment, Games and 20 other categories.

2 Meta Keywords hasn't got a lead over HTML5 DocType in any websites category.

Geography

1 HTML5 DocType is leading in most countries, including United States, Japan, China, Germany and 162 other countries.

2 Meta Keywords hasn't got a lead over HTML5 DocType in any country.