According to Defenders of Wildlife, male killer whales grow up to 23 feet in length and weigh from 7 to 10 tons. Female whales grow up to 23 feet when fully grown and weigh anywhere from 4 to 6 tons.
Killer whales are typically slightly smaller than a bus when fully grown. A baby killer whale, known as a calf, weighs up to 400 pounds at birth. Newborn calves measure up to 7 feet.
Although male killer whales are typically larger than females, the latter lead the mammals' family groups, which are called pods. Also known as orcas, killer whales are an endangered species.