I am 5'7", 160 lbs, and a size 8 in pants usually. This doesn't have a size chart so I got my size 8 and it fits exactly as expected! I love bike shorts, but I prefer the soft yoga lounge style versus the athletic compression spandex material. So with that, its always a gamble when you get lighter colors. I got the light blue in these and they are not see through! I am very impressed. The material is thinner though, so you can definitely see panty lines, but it's not see through which is great! See full review