I never really drank many stouts. They hare fairly heavy and a little bitter. I am starting to like them. The oatmeal gives it a creamy smoothness and mouth feel. I should have tested this. I bet it is 7% or so.
Stand up fast and shake your head side to side 3 times quickly. If you wobble but don’t fall over, it is 6-7%. If you have to grab something to keep falling over, it is 7-9%.