Shoes run at least 1/2 to 1 size bigger.  I am almost always a 10.5 in all my shoes and it suggested i pick the 10.5 based on previous purchases so i did.  I was super bummed when i got them, they are too big! I don't think i have ever bought Adidas shoes so i was not sure about the sizing.  I took a picture of the insole and my foot on top of it so you can see the difference.  I am a 10.5 in the Saucony cohesion 10's and Nike flex fury as well so you get an idea.  I will have to return these.  I am not sure if i exchange them for a smaller size, i might try them on at a store and re order at some point.  Even though they run big, the shoe feels nice and cushioned inside.  The shoes also look really nice.