I have really skinny feet and usually wear a 9.5. After reading the other reviews I decided to take a shot at the 10s instead. It was a good idea and they are still a bit snug. I have only worn them twice and they are already starting to stretch out a bit so they will be fine. Great for the price. I'd say go up a half size for sure or maybe even a full size if your feet aren't REALLY narrow.