I'm 5'3 and weigh 227 pounds, therefore I'll wear a size 1X or 2X. Since several commenters mentioned that the smaller you go, the tighter it is around your waist, which is really practical and easy to breathe, I chose to get an extra large. It may cause discomfort. For two weeks, I make sure to cover it with a T-shirt to prevent the scratching sensation. It was incredibly useful when I was working out, but I failed at it. I'm definitely looking at other things to buy.