I wear a size Xtra Small, but I have yoga pants cut off by the knees that say Small. So I thought these pants might work as a Small for me too. But they weren't very successful. If you are looking for yoga pants that are tighter, assuming you are petite and xtra small, then these are definitely not a good choice. Although, I weigh 97 pounds and I am 5'4. My friend who is around 5'7 and 120 pounds fit into the Small size perfectly. If you are my size I do not recommend these pants. If you are not looking for a tighter yoga pant and your size is from a 2-4 then these pants in a small should work.