You must be wondering which major sites use WordPress? From small blogs to big businesses, all use WordPress for different purposes. Even my site is built on WordPress. To be specific below are some big entities that use WordPress to power its online presence. This covers Universities, Fashion, News sites and Celebrity sites to mention a few:
Fashion / Entertainment / Auto / Nonprofits
Globally recognised fashion and lifestyle magazine Vogue, Toyota Motors, The Obama Foundation, world’s leading producers and providers of entertainment and information The Walt Disney Company use WordPress as their Content Management System
Vogue 
Toyota Motors Brasil 
The Obama Foundation 
The Walt Disney
Universities
When it comes to Education, WordPress has many plugins available that allows extending the default WordPress offerings and meet Education institutes demands. This is the reason why Georgia State University, The University of Mary Washington, University of Missouri College of Engineering, etc proudly power their sites using WordPress.
Governments
The White House is using WordPress since December 2017. The official website of Prime Minister’s Office, Government of India uses WordPress
PM India Cares 
The White House USA
Celebrities
The World’s Fastest Man, for that matter, has his own site running on WordPress.
Katy Perry is a multi-platinum American singer-songwriter and musician. Katy Perry’s website is running on WordPress
News
American weekly news magazine published in New York City called Time and Facebook which you use on day to day basis, it’s Facebook News site are built on WordPress. WordPress is trusted by content publishers both large and small including CNN and the NY Times.
WordPress showcase page covers exhaustive list of sites that use WordPress.
