Dog bed size.

Worked example

A dog that is 28 in from nose to base of tail and sleeps stretched out needs a bed at least 28 + 8 = 36 in long, which is a Large (about 36 x 27 in). If the same dog sleeps curled up, 28 + 4 = 32 in is enough, and a Large is still the nearest size up.

How it works

Bed makers size beds to the longest the dog lies. A dog that stretches out needs the full length plus about 8 inches; a curler needs the length plus about 4 inches, and does well in a nest or bolster bed. If your dog sits between two sizes, take the larger one: a dog can curl in a big bed but cannot stretch in a small one.

Sizes used, typical retail (length x width): Small 24 x 18 in, Medium 30 x 20 in, Large 36 x 27 in, X-Large 42 x 30 in, XX-Large 48 x 36 in. Brands vary by an inch or two, so check the sleeping surface of the exact bed, which is smaller than the outside of a bolster bed. Chew-prone puppies are better in a cheap bed until they grow.

Sources and basis (checked 2026-10-05): the nose-to-tail-plus-allowance rule as used in pet-retailer bed sizing guides, and typical retail bed dimensions. Neither is a formal standard.

FAQ

What size dog bed do I need?

Measure from the nose to the base of the tail. Add 8 inches for a dog that sleeps stretched out or 4 inches for a dog that curls up, and choose a bed at least that long.

How do I measure my dog for a bed?

Stand the dog and measure from the tip of the nose to the base of the tail, not the tail tip. Measure how they actually sleep too: curled or stretched out.

Should I size up a dog bed?

Yes, if in doubt. A larger bed still works for a curled dog, but a bed that is too small leaves a stretching dog hanging off the edge.

Does dog bed size depend on weight?

Weight is only a rough guide. Two 60 pound dogs can be quite different lengths, so length is the better measurement.

What size bed for a large dog?

Large dogs of about 50 to 90 pounds usually need 36 to 42 inch beds, but go by the length measurement.