What is the proper size kennel for my pup?

Deciding on a kennel size by weight works fairly well, but a more accurate method is to measure your pup's actual height and length. Add 2 to 4 inches to determine the best size kennel. A proper sized kennel simulates a natural den environment. Too small and they will be cramped, hitting their head on the ceiling and not able to turn around. Too large and they will feel less safe and secure.