I wear size 13 tennis shoes. I had to exchange them for a larger size after getting a size 14. So now I'm waiting for a size 15 to see if they fit. My toes really hurt. UPDATE: I WANT TO WARN YOU ALL; IF YOU DRY THIS SHOE AS PROVIDED, YOU WILL REGRET IT. I HAD TO WASH THESE SHOES 3 TIMES IN A ROW TO REMOVE THE ACID ODOR FROM THE DRYER. I ended up having to dry them gently hoping they wouldn't shrink just to get dryer sheets to stop the smell. it worked. but they sat down