im pretty sure artifacts have size, but i don't see any way to see how much each of them have. it would be very useful to have that # in the artifacts tab. if artifacts dont have size forgive my noob request.

All artifacts take up a single space unless it specifies otherwise. Note that if an artifact has more than 1 "use", the size is multiplied by the number of uses. So, a typical artifact with 2 uses will take up 2 spaces.