I love these and they last for a long,long time! Comfortable, durable and again long wearing so it's money well spent. Do check their chart as "sock size" and "shoe size" do not mirror each other; a 10-12 sock size is smaller than a 10-12 shoe size & they won't have the over-the-calf stretching; fyi.  Contact them if you're not sure; I've never had a problem with shrinkage after many washings & dryings so getting a bigger size is fine, but I would not expect them to shrink to fit if you get much too big of a size (again recommend contacting them if you're just not sure). Summarily when you get that figured out; you'll probably buy these annually and never have to worry about getting the best over-the-calf sock at the best price anymore.