Option #1: When logged in, go to {domainname}/wp-admin/about.php – there you can see what is the current version of your WordPress site. On that page, you can also see other information such as new releases if you’re currently using an older version.

Option #2: When logged in, click Dashboard if you’re not yet there, and scroll down to the at “At a Glance” section. From there, you can see the current WordPress version used as well as other important information.