How to Pick the Right Dog Door Size

How to Pick the Right Dog Door Size

A dog door gives both the owner and his dog freedom. The dog can go in and out of the house at will, and the owner has flexibility in his schedule -- no more running home to let pets out. A dog door does not need to be the exact size of your dog for your pet to fit through it comfortably. Here are the top tips for buying a pet door for your home.

Choosing a Dog Door Size:


Measure your dog’s width.

Use a tape measure to determine the widest part of his body, typically his shoulders, just below his neck. Sometimes the hips are larger, so measure just above the back legs.


Measure your dog’s height.

Start at the top of his shoulders and move down to his paws. Your dog can crouch, so this is just a general guide for the height of the door.


Weigh your dog.

The dog’s weight may affect what kind and how durable of a dog door you should purchase, such as an electronic dog door or electromagnetic dog door for a larger dog. Dog flaps might also work for a small dog.


Practice with a cardboard flap.

Get a large, sturdy cardboard box. On one side, cut out a cat or dog door slightly wider than your pet’s width but shorter than their height. Place a treat in the box and see if your dog can get through the opening.


Adjust the cardboard door by making it slightly larger.

You can also start fresh on another side. The goal is to make the doggie door as small as possible without making it too small for your dog to successfully and safely get in and out.


Select a doggie door closest in size to the cardboard door.

The height of the doggie door may be adjustable, so read the specifications carefully, including the weight requirements of your pets. This chart will give you a general idea of what size to shop for, but not all manufacturers label doors the same. The larger the door, the more likely you will want one that can lock or that is only opened with a sensor on the dog’s collar.

Dog Weight Approximate Dog Door Size
Up to 15 lbs Small
Up to 40 lbs Medium
Up to 100 lbs Large
200+ lbs Extra-Large