WordPress Dominates the CMS Space
According to technology survey firm W3Techs, the content management platform (sometimes referred to as experience management) now powers upwards of 30 percent of websites - a 5 percent increase in the past two and a half years.
That's a significant increase in the past few years and it indicates not just the popularity of the system but the increased usage of such systems in general. What is really important here is that the data point relates to the entire Web, however, and not just those whose website uses a CMS (content management system).
When it comes to the actual market share, the dominance of WordPress becomes quite evident. WordPress claims slightly over 60 percent (up slightly from November 2015's number of 58.7 percent). The nearest competition? Joomla with 3.1 percent market share (up from 2.8 percent). Drupal is also up from 2.1 percent to 2.2 percent.
It’s also important to note that for the purposes of this study, “WordPress” refers to both the non-hosted open source blogging software that is downloaded and installed, and the hosted WordPress.com platform. Also worthy of note is that the data wasn't really broken down by the popularity of websites which could provide a great deal more insight. WordPress is often used by less popular sites so it's dominance in the top 1000 or 10000 sites is likely far less.