Bullmastiff

Across 36 single-size giant breeds, a lifespan midpoint of 8 years is about 2.2 years shorter than the 10.2-year average. A midpoint adult weight of 115 lb is about the same as the 116 lb average for those giant breeds.

The listed origin is England. The coat is described as smooth, short. The AKC energy score is 4 out of 5, 0.3 points above the group average of 3.7 for the Working Group. Shedding scores 3 out of 5. Grooming scores 1 out of 5, so home brushing covers most weeks. Trainability scores 4 out of 5, which is a biddable score. Good with children scores 3 out of 5. Good with other dogs scores 3 out of 5. AKC ranked this breed number 78 in 2025.

Adult size is usually reached in up to 24 months (size-band statement (Salt et al. 2017): larger breeds require up to 24 months). AKC parent-club recommended health screenings: Hip Evaluation, Elbow Evaluation, Cardiac Exam, Ophthalmologist Evaluation, and Thyroid Evaluation. These are screening tests, not a list of diseases the breed is guaranteed to develop.