I don't know what to do with the size. I'm a solid size 12 for life, but those 12s felt like 13s or more. I also have a wide foot so I bought a large size. and it still felt tight on the sides (since they assumed a wider foot required a longer shoe?). So long on top and neat on the side. I've never experienced that with 12W. They're light and comfortable, but I really don't know what to advise others about sizing. except luck? Not worth swapping out, I wanted them for a quick (but decent) shoe to put on and take off for short trips around the garden (no pool shoes etc). But they do adjust a bit on the sides to make it quick, which is what I expected. I will make them work.