Known also as the English Mastiff, this is the heaviest dog breed in the world — a massive, slow-moving guardian with an ancient British lineage and a notably placid temperament.
Large mastiff-type dogs were recorded in Britain by Roman writers, who noted that British war dogs were exported to the arenas of Rome.2 Through the medieval period the type served as an estate guardian, a hunting dog on large game, and — less creditably — in bear- and bull-baiting until those were banned in 1835.
Numbers collapsed twice in the twentieth century: British breeding all but ceased during both World Wars, and after 1945 the breed was reconstituted largely from dogs that had been exported to North America.3 The Old English Mastiff Club, founded in 1883, produced the first standard; the AKC recognised the breed in 1885.1
"Mastiff" most likely derives from the Latin mansuetus, meaning tame or domesticated, by way of Old French mastin. An older and less supported folk etymology proposed masty, meaning powerful. The AKC uses the bare name Mastiff; elsewhere the qualifier "English" distinguishes it from the Neapolitan, Tibetan and other mastiff breeds.2
| Life expectancy | 6–10 years |
|---|---|
| Height — male | 30 in and up (76+ cm) |
| Height — female | 27.5 in and up (70+ cm) |
| Weight — male | 160–230 lb (73–104 kg) |
| Weight — female | 120–170 lb (54–77 kg) |
| Coat type & colors | Short, coarse outer coat over a dense undercoat; fawn, apricot or brindle with a black mask |
| Shedding | Moderate to heavy |
| Exercise needs | Low to moderate — steady walking, no forced running |
| Country of origin | United Kingdom |
| AKC group | Working Group (AKC) |
| Prestige Breed size class | Large Breed · Over 60 lbs |
The AKC describes the Mastiff as courageous, dignified and good-natured.1 The breed standard emphasises a combination of grandeur and gentleness; a sound Mastiff is calm, slow to react and physically undemonstrative in a way that distinguishes it from most guarding breeds.
Mastiffs guard by presence rather than by action, and a stable individual will position itself between family and stranger without escalating. They are sensitive to correction and to household tension. Drool, snoring and a considerable capacity for sedentary companionship are all part of the package.
The heaviest dog ever reliably recorded was an English Mastiff named Zorba, documented in the early 1990s at over 340 pounds and more than eight feet from nose to tail.2
A Mastiff puppy can gain over a hundred pounds in its first year. Restrict stairs, jumping and forced exercise, and feed a controlled large-breed growth diet.
GDV is a leading cause of death in giant breeds. Discuss prophylactic gastropexy and learn the emergency signs.3
The shortened muzzle and sheer mass make heat dangerous, and giant breeds require breed-aware anaesthetic protocols.
A dog that will finish at 200 pounds must learn leash manners and door behaviour as a puppy.
This guide is educational and is not veterinary advice. Breed standards, measurements and health information are drawn from the sources listed above; consult your veterinarian for guidance specific to your dog.
Prestige Breed makes a large breed multivitamin designed for breeds like the Mastiff — see the Mastiff Multivitamin.