Size is apparently "pot luck". This is my second pair. The first pair fit perfectly and felt great but actually stretched out over several months and became loose fitting causing the toes to catch and fold under creating a danger of falling so it became time for replacement. Since the first was a perfect fit in the beginning I reordered in the same size. The new pair are slightly shorter, more narrow and a very poor fit. They are marked the same size as my first pair but they are smaller overall. They also left a black stain on only my right foot the first day. Too bad because I loved the first pair and I would have continued to order these forever. If you are lucky enough to get a pair that fits you'll love them too. Just dont count on the next pair fitting the same. Well worth the money if you get a good pair. Worthless if you dont. Anyway, I'll give it a couple more weeks and see if they stretch into shape and fit better. If so maybe I'll change my rating.