Developed in Germany, the Boxer is a breed of stocky, medium-sized, short-haired dog. The coat is smooth and fawn or brindled, with or without white markings. Boxers are brachycephalic (they have broad, short skulls), and have a square muzzle, mandibular prognathism (an underbite), very strong jaws and a powerful bite ideal for hanging on to large prey. The Boxer was bred from the Old English Bulldog and the now extinct Bullenbeisser and is part of the Molosser group.

Boxers were first exhibited in a dog show for St. Bernards in Munich in 1895, the first Boxer club being founded the next year. Based on 2011 American Kennel Club statistics, Boxers are the seventh most popular breed of dog in the United States for the second year in a row, moving down from sixth where they were ranked for the previous three years.