I bought the size that I always wear and used the test method on hiking boot sizing (Toes to the end of the shoe, thumb fits between heal and boot) and they fit fine.  I have been wearing them around the home, shopping, etc. and the feel great.  The hiking test comes in about a month, but I feel confident they will work great.  My feet are sensitive to the shoe.  After earing these for a few days, all day long, my feet feel great once removed in the evening.