I'm 5'8" tall, about 320lbs, size 48 waist, i got the 2xl and they're still kinda big. Not very much along the lines of compression, but they still hug the fat and stay above the waist line. I do a lot of walking because of taking the bus everywhere and i like to wear them under my shorts, over my socks. They help keep my socks taught and keeps them from rolling downand still adds a bit of compression ( not as much as I'd like) with coolness when the summer breeze blows by.