One size fits all? Hardly. Yet these managed to fit enough to keep. I'm usually a comfortable LG on bottoms with my big girl thighs, at 5'4" 135lbs with 36" hips the harem fit is passable--enough for my casual self to enjoy some casual yoga and wear. To me, the pants are close to a Target SM or Forever21 LG if that helps. Wish they could be a bit larger, but for the comfort I'm pleased. Soft and highly flexible material. You don't get a full harem effect (the whole diaper crotch), yet I think it looks more reasonable because of it. Worked for yoga, many compliments.