Even though you can expect some degree of adjustability with your new dog
collar, it is important to measure your dog carefully.

If you are satisfied with the fit of your dog's current collar,
measure that collar from the center bar of the buckle to the farthest
hole. Our collars are sized according to this measurement, not to the
over-all length of the collar, which varies by manufacturer and by
whether it is a buckle-end or a dee-end style collar.

If this is your dog's first collar or you need a collar in a different
size, measure around the dog's neck with an allowance for 2 fingers to fit
between the dog and the collar. The collar shouldn't be so tight that it
will cause discomfort or so loose that it slides over the dogs head.