The Mastiff, also called the English Mastiff, is a massive, heavy-boned guardian with a broad head, dark mask and short fawn, apricot or brindle coat. Its ancestors guarded British estates for centuries, and the modern breed nearly vanished after World War II before a handful of dogs rebuilt it. Adults commonly weigh from about 120 to 230 pounds.
Most Mastiffs are calm, dignified and gentle at home, with a quiet protectiveness toward their people, though every dog varies. They're more couch-loving than athletic, but size changes the math: early training, sturdy gear and a budget for giant-breed food and vet care all matter. Lifespans run shorter than in smaller breeds, often six to ten years, so plan for the senior years early.