Developed in 19th-century England as a guard dog. By the early 1900s gamekeepers used it to help stop poachers.

The Mastiff & Bull family. Heavy-boned guardians and the bull breeds descended from them. Powerful but often gentle at home, they need early training and socialization.

Affectionate, loyal and brave.

Voice

Barks to alert you, then settles.

With kids

Good with respectful kids when raised with them.

Other dogs

Usually fine with other dogs when socialized.

Home

Best in a house with a yard.

Exercise. Moderate: daily walks and active play, such as a game of fetch. Puppies do better with several short sessions than one long walk, and older dogs need gentler outings.

Training. Trains at an average pace. Reward-based methods and a regular routine work best.

Short, smooth coat: a weekly once-over with a rubber curry mitt or bristle brush and an occasional bath. Light shedding.

For every dog: trim nails when you can hear them click on the floor, brush teeth daily if you can (a few times a week still helps), and clean ears about once a month, drying them well after baths and swims.

Daily calories

About 1,960–2,380 kcal for a healthy adult

Dry food

Roughly 5–6 cups a day at ~400 kcal per cup

Puppies eat four small meals a day at 6 to 12 weeks, drop to three somewhere between 3 and 6 months, and move to two meals a day from about 6 months.

Large-breed puppies can take 15 to 24 months to finish growing. Ask your vet about a large-breed puppy food, and check before adding any supplements.

Deep-chested dogs are at higher risk of bloat (GDV). Feed two meals a day rather than one, use a slow feeder if your dog gulps, and keep mealtimes calm.

Keep treats, including training treats and table scraps, under 10% of daily calories.

Calories use the resting-energy formula from the Merck Veterinary Manual (70 × body weight in kg^0.75) times a maintenance factor of 1.4 to 1.8, so very active or working dogs may need more. Cups assume about 400 kcal per cup; check your food's label. Treat any feeding chart as a starting point and adjust to body condition.

Typical lifespan is 9–11 years. Conditions reported in the breed:

Ask breeders for health-test results from the parents (hips, eyes, and DNA tests where relevant), and schedule yearly vet checkups.

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Photos come from Wikimedia Commons and are used under the licenses shown. Only freely licensed photos appear on this site; where none is available, you'll see an illustration.

• Wikipedia: Bullmastiff (opens in a new tab)
• AKC breed weight chart (opens in a new tab)
• AKC: Puppy feeding fundamentals (opens in a new tab), bloat (opens in a new tab), treats (opens in a new tab) and grooming (opens in a new tab)
• Merck Veterinary Manual: Nutritional requirements of small animals (opens in a new tab)

Ratings for energy, shedding and the like are our own summaries, informed by these sources. Breed facts were checked in October 2026.