I have no idea. Everybody tells me different things. Some say I look my age, some say I look older, some say I look younger. I think it also depends on how short my hair is at the time.
I always get asked for ID, but in the UK it's the law that everybody does until they look over 25.
I'm 22, about to be 23 in the fall. I still get asked for ID at bars all the time, and sometimes whenever I go out to things/events, they'll ask where my parents are because I look 16 and not responsible enough to make purchases and such.
In a way it is annoying, but I'm glad I look young because hopefully that'll mean that I will age well.