How do to know if a site is WordPress? and what theme are they using? Here are some websites that will check if their sites are using WordPress and also tells you what theme they are using and what plugins .. Very useful if you find a website that you like and want to see if it is related to WordPress and maybe see what theme is using. So in addition to checking the footer of the website to build with WordPress, or checking the source code. Click on any WordPress checkout website below to find out if the site is built with WordPress CMS. Easy to follow tutorial with step-by-step instructions on how to start a blog or how to make a website with WordPress with build in drag and drop page builder.