The American Mastiff is a very unique dog, and well beloved by their owners. They have some very distinct characteristics and traits. Mastiffs are very powerful, massive dogs, and one of the largest dog breeds. They have a very heavy and wide head that is rather rectangular in shape. The ears sit high on their heads and are rounded in shape. Their eyes are an amber color and are preferred to be dark. Their medium sized muzzle has a black mask and is well proportioned to their head. The American Mastiff is the product of an outcrossing, in the early development of the breed, between the English Mastiff and the Anatolian Mastiff. This also produced a drier mouth than many of the other Mastiff breeds because their lower lip line is tighter and more defined. The selective breeding that followed kept this trait in this breed of Mastiff dog.



The American Mastiff has a very strong neck which is slightly arched, with a black nose and a scissored bite. They have a rounded, broad chest which descends down to the level of the elbows. Their ribs spread back broadly and extend a long distance into their straight and muscular back. Their muscles are well defined down their forelegs which are straight and set wide, as are their hind legs. They have huge feet and arched toes. The tail is long and thick.

The American Mastiff dogs develop in a variety of colors including fawn, brindle and even apricot. Most puppies are born dark in color and tend to lighten up as they get older. Some hang onto their darker color while others actually become a very light fawn color by the time they turn one year old. In this breed of Mastiff dog, white markings on their chin or nose, and chest and feet are acceptable. They are generally calm and quiet dogs. They are loyal and loving dogs who are not usually aggressive unless they need to protect their masters.

Though you would not think so at first glance, the American Mastiff is very good with children and makes a great family dog. They are, again, not known for being aggressive unless they are in a circumstance where their family, and their family's children, are threatened. They will become intimidating defenders in this case, and even courageous. They are loyal to their owners, and are gentle companions, patient and loving, especially with children.

The males can weigh between 160 and 200 pounds. The females range from 140-180 pounds. And their height usually ranges from 28 to 36 inches. Because they are so large, they need to be handled by an owner who can be firm and strong in their leadership.

Even though American Mastiff dogs are of the largest breeds, they don't tend to be plagued by many of the health problems that are common in other larger breeds. In fact, they are generally healthy and happy dogs. And, contrary to some other large breeds, this breed of Mastiff dog will get along perfectly well in an apartment as long as they are exercised daily. This can be a daily walk or short run. Usually even a small fenced yard will do just fine as they tend to e a little on the lazy side as they get older.

Though they probably wouldn't choose to exercise daily, a steady routine will keep them more fit and happier. It is good for their mental and physical health to be out and walking regularly. And, of course, a leashed walk in public is best. The American Mastiff generally lives 10 to 12 years.

Their grooming is easy due to their short-haired and smooth coat. They can easily be shampooed and shined by drying them after bathing, then brushing their coat with a brush with firm bristles. Though they do shed, it is average, not out of control.

This dog breed is not for everyone, but for the right owner or family, they are loving, and loveable companions, which can be surprisingly docile and gentle.