They will pack out just a bit. but not much. When you stand in them and bend you knees, you want your toes to be touching the end. If this is the case and it feels sung you are stoked. That is a perfect fit.

Thanks for the tip! I tried them with my usual snow socks and they were squeezing my toes before I even stood up. Guess these will have to go back, but at least now I have a better idea on how they should fit. Thx