These boots are fantastic.  Comfortable and warm on long dog walks.  I usually wear a 7 to a 7.5.  I ordered a 7.5 and they are roomy.  My heel slips up a little bit sometimes while walking in them, but they would probably fit perfectly with thicker socks.  I have a slightly wide foot, and they fit well.  They can be pulled on and off without unlacing, which is great when running in and out to take the dogs out or start the car in the morning.