One in four websites is now powered by WordPress.

Today is a big day for the free and open-source content management system (CMS). To be perfectly clear, the milestone figure doesn’t represent a fraction of all websites that have a CMS: WordPress now powers 25 percent of the Web.

The latest data comes from W3Techs, which measures both usage and market share: “WordPress is used by 58.7% of all the websites whose content management system we know. This is 25.0% of all websites.” While these numbers naturally fluctuate over the course of the month, the general trend for WordPress has been slow but steady growth.

http://venturebeat.com/2015/11/08/wordpress-now-powers-25-of-the-web/