So I'm an idiot and ordered size M (I think it's a man's size) which didn't matter that much. thick, so that's fine. I am currently a women's size 6/7, 5'7 1/2 and 132 pounds. So if you are smaller, definitely choose the small ones. Also, the belt does its job and keeps my pants in place, doesn't look very cheap either. I am very happy with this belt!