I bought size S, I'm a female, 5ft 7in, 128lbs. This robe fits me exactly the way I want it. right above the ground. Its sleeves reach to the ankles and it is very soft. It also fits my husband who is 5ft 9in, 175lbs, 44in shoulder width. It reached to his ankles, the sleeves reached to the knuckles of his thumb and it looked tailor made for him. So I would say if you are between these sizes it will fit you perfectly. If less, it will be too big, if more, then one size more.