Crate size by breed / Working group
Mastiff crate size
An adult Mastiff at 180–190 lb is heavier than the largest band in the manufacturer's chart (110 lb), so the answer is a 54 in crate and a tape measure rather than a chart row.
Which crate for a Mastiff
The chart below is MidWest's iCrate sizing, the most common wire crate in US pet stores, with the Mastiff's weight range marked. Interior lengths are the figures the manufacturer lists, not the nominal size, which is why a "36 in" crate is 36.6 in inside.
| Crate | Label | Interior L × W × H (in) | Dog weight | Mastiff |
|---|---|---|---|---|
| 18 in | Toy | 17.68 × 11.7 × 14.22 | 1–6 lb | Too small |
| 22 in | Extra Small | 22.5 × 14 × 16 | 7–12 lb | Too small |
| 24 in | Small | 23.6 × 16.7 × 19.1 | 11–25 lb | Too small |
| 30 in | Medium | 29.7 × 18.6 × 21 | 26–40 lb | Too small |
| 36 in | Intermediate | 36.6 × 21.9 × 24.5 | 41–70 lb | Too small |
| 42 in | Large | 41.9 × 29.5 × 30.3 | 70–90 lb | Too small |
| 48 in | Extra Large | 47.76 × 29.6 × 31.7 | 90–110 lb | Too small |
Crate dimensions and weight bands: MidWest Homes for Pets — iCrate product sizing (manufacturer), checked 2026-10-20.
Measure before you buy
Weight bands are a shortcut. The dimension that decides whether a crate works is body length. Stand the dog, measure from the tip of the nose to the base of the tail (not the tail tip), and add 2 to 4 inches; the crate's interior length must be at least that. For height, measure from the floor to the top of the head while sitting and add the same allowance.
The welfare rule is the one every shelter and trainer repeats: the crate must be large enough for the dog to stand up and turn around. Bigger is not better for house-training, because a crate with spare floor space invites the puppy to soil one end and sleep in the other, which is why the adult-size crates in this chart ship with a divider panel.
Puppies: buy the adult size and use the divider
A Mastiff puppy reaches 190 lb at maturity, so buying a puppy-sized crate means buying twice. Choose the crate for the adult weight above, fit the divider so the puppy has room to stand, turn and lie down and no more, and move the divider back as the dog grows. The Mastiff puppy feeding chart shows the growth stages the divider will follow.
Bed size for a Mastiff
Using Orvis's rectangle-bed fit guide, a 190 lb Mastiff takes the X-Large (53 × 35 in). Dogs that sleep stretched out need the length of their body plus a few inches; curl-sleepers can go one size down in a bolster bed. Full chart on the bed size page.
How the Mastiff compares
By mid-range adult weight, the Mastiff ranks 49 of 49 breeds on this site, with 0 heavier and 48 lighter — a giant breed in the size classes used here. Standards specify neither height nor weight; figures are the usual ranges reported.
Breeds of similar weight, whose crate answer is the same or one size off: Saint Bernard (120–200 lb), Newfoundland (143–176 lb), Great Dane (110–180 lb), Great Pyrenees (120–165 lb), Rottweiler (110–132 lb).
Adult height from Wikipedia breed infobox/body; adult weight from Wikipedia breed infobox/body; both checked 2026-10-20. Height is at the withers in inches; weight in pounds for adult dogs. Where a breed standard states a figure it is used first (AKC, then FCI); where the standard is silent, the Wikipedia infobox or VCA breed page is used and named. Metric figures were converted and rounded to the nearest half inch or pound. Where the source gives only a maximum, the range reads "up to" that figure.