I usually wear an 8.5 in athletic shoes and a 9 in sandals & flats. I ordered a 9 in these and they were somewhat smaller than expected. Had I tried them on in a store, I would've gotten an 9.5...which I never wear. The strap across the back rubbed my heel a bit, but it may not have had the sizing been correct. I hope it gets softer with wear. The shoe and materials are super cute.