I am 5'4" and 128 pounds, the small/medium size fits just right - the leggings are very stretchy and not tight at all, and they hug my body very well!  They are also thick and have very soft linings inside, so good for colder days!  The washing instruction is that they have to be washed in  cold water by hand, so I certainly won't toss them into the washer and dryer.  I really love these leggings as they are fashionable, affordable and comfy!