I wear a size 7 shoe.  I get Keens--which I have a lot of--in size 8 because I like wearing two pair of thick wool socks, plus an insert.  I got these in 8 1/2, due to what others recommended.  I can only wear one pair of wool socks and no inserts with them.  Yes, size up a full size in these of you want comfort and no blisters.  I really like these boots!  I like all of the Keens that I have purchased but I like these the best!