I bought these on a recommendation from a female friend who loves them. I have women's size 9 feet and they're too big. I was hoping they would fit even though I know men's size 9-11 is too big - so that's my fault. If you wear women's size 9, don't buy them. I would say they'd fit women's size 11+. The material is comfortable and they don't slip off the heel no matter how much I move around. They're thin but not too thin. I really like them, I just wish they fit!