What Size Dog House Do I Need?
Wondering what size dog house you need? This free dog house size calculator takes your dog's height and length, applies the standard outdoor sizing rules, and recommends the right interior dimensions — plus the right door opening. Note: this is for an outdoor dog house, not an indoor crate; an outdoor house is sized snug so your dog's body heat keeps it warm. For an indoor den, use the dog crate size picker instead.
Enter your dog's measurements
Your results
| Interior height | — |
|---|---|
| Interior length | — |
| Interior width | — |
| Door opening (H × W) | — |
Sizing guidance based on standard outdoor dog house conventions — not a substitute for professional advice.
How to use this calculator
Have your dog stand normally and measure two things in inches: height — from the floor to the top of the head or ears, whichever is taller — and length — from the tip of the nose to the base of the tail (don't include the tail). Enter both above and the recommended interior dimensions update instantly. The calculator also gives you a correctly sized door opening, which matters as much as the box itself.
How it works
The sizing rule this calculator uses is the one dog house manufacturers follow: the interior height must be your dog's height plus 6 inches so they can stand without crouching, the interior length must be your dog's length plus 12 inches so they can lie fully stretched out, and the interior width must be your dog's height plus 6 inches so they can turn around.
Unlike an indoor crate — where a divider can shrink the space — an outdoor dog house should fit snugly: your dog's own body heat is what keeps it warm, and a house that is too big never heats up. That is why the rule adds clearance for movement but stops there.
Example: a dog that is 24″ tall and 24″ long needs an interior height of 24 + 6 = 30″, an interior length of 24 + 12 = 36″, and an interior width of 24 + 6 = 30″ — in other words, a 30 × 36-inch house, 30 inches tall.
Door guidelines: the door opening should be about dog height minus 2 inches tall (never less than 75% of the dog's height), and about 60% of the dog's height wide. For the 24″ dog above, that is a 22″ × 14.5″ opening. A low, narrow opening keeps wind, rain, and drafts out while letting your dog pass through comfortably.
Buying tip: store-bought dog houses come in standard sizes, so pick the smallest house whose interior meets or beats all three dimensions. Leave 2 inches of clearance under the roof for bedding, and raise the house a few inches off the ground so the floor stays dry.
Frequently asked questions
What size dog house do I need?
Measure your dog's height (floor to the top of the head or ears) and length (nose to the base of the tail) in inches. Add 6 inches to the height for the interior height, 12 inches to the length for the interior length, and 6 inches to the height again for the interior width. So a 24-inch-tall, 24-inch-long dog needs a house about 30 inches tall with a 30 by 36-inch floor. The house should be big enough to stand, turn around, and lie down in — but snug, not roomy.
Should a dog house be big or small?
Neither — a dog house should be just big enough. Your dog's body heat warms a snug space, so an oversized house stays cold in winter. Size it so your dog can stand without crouching, turn around easily, and lie stretched out — then stop. If you are between two store sizes, pick the smaller one as long as it still passes the stand-and-turn test.
How big should the dog house door be?
The door opening should be about 2 inches shorter than your dog's height — so a 24-inch-tall dog gets a 22-inch-tall door — and about 60% of your dog's height wide (roughly 14.5 inches for that same dog). Never make the door taller than the dog: a low, narrow opening keeps wind and rain out while letting your dog slip through comfortably. Keep the bottom of the opening a couple of inches above the floor so bedding stays inside.
How do I keep a dog house warm in winter?
Snug sizing is the biggest factor — body heat only warms a close space. Raise the house a few inches off the ground on feet or a pallet so the floor is not sitting on frozen earth, add a heavy door flap or curtain to block the wind, and use dry straw or a raised dog bed rather than blankets that mat down. Face the door away from the prevailing wind, and in extreme cold bring the dog indoors — no outdoor house replaces real shelter in a hard freeze.