These boots fit very much like the portsmouth series shoes with a thicker sole. I got a 10.5 and they fit roomy in the toe box and wide as Keens normally do. Took about 15-20 hours to break them in, they were a bit uncomfortable for the first few wears but nothing too crazy. Keep my feet dry, they aren't designed for winter and I am wearing them in winter.. so my feet are a little cold in them.. but not too bad. I will just keep buying these forever..