These shrink A LOT, which means the waistband will end up being a little too big if you size up. My boyfriend wore out a pair of medium pj pants, but they were a little too small. He probably could have used a large. I got him an XL in this pair, and after washing, they fit pretty well. He's got very muscular thighs, and these fit well. The waistband is a little loose, but the length is perfect. They're soft, comfy, and wash well. They're also a nice light blue. Just be sure to size up.