My first order (medium) fit my feet perfectly, but I wish I had followed the advice of some of the reviews and ordered a size larger because their big toes quickly started poking through the sock. I now have the large size, and that eliminates my concern. The socks are very comfortable and soft. I especially appreciate the flat band that goes around my feet. Some other brands of socks have a rough, braided elastic that goes around the feet. One way to improve the sock is to work on making the toe seams softer and flatter because after a few hours, they become quite uncomfortable.