I first ordered the S/M, which I had to return because they were smaller than expected and far too tight for me. The L/XL fit great around the calf, but super tight around my ankle. So tight it would have affected circulation. I have slender ankles. I wanted the calf compression for exercise as I have shin splint. I work in a hospital and use the Physix compression socks L/XL, which are fabulous. Very easy return though. Great Amazon service.