Warthogs range in size from 0.91 to 1.5 metres (3.0 to 4.9 ft) in length and 50 to 150 kg (110 to 330 lb) in weight. A warthog is identifiable by the two pairs of tusks protruding from the mouth, which are used as weapons against predators. The upper canine teeth can grow to 23 cm (9.1 in), and are of a squashed circle shape in cross section, almost rectangular, being about 4.5 cm (1.8 in) deep and 2.5 cm (0.98 in) wide. The tusk will curve 90 degrees or more from the root, and the tusk will not lie flat on a table, as it curves somewhat backwards as it grows. The tusks are used for digging, for combat with other hogs, and in defence against predators—the lower set can inflict severe wounds. Warthog ivory is taken from the constantly growing canine teeth. Each warthog has a pair of teeth in each jaw with the lower teeth being far shorter than the upper teeth. Both pairs grow upwards, with the upper teeth being by far the more spectacular in appearance. The lower pair, however, are the more dangerous: the teeth are straight, sharply pointed, and keep a keen edge by the upper pair rubbing against the lower pair. The tusks, more often the upper set, are worked much in the way of elephant tusks with all designs scaled down. Tusks are carved predominantly for the tourist trade in East and Southern Africa. The male is called a boar, the female a sow, and the young piglets.
Although warthogs are commonly seen in (and associated with) open grasslands, they will seek shelter and forage in denser vegetation. In fact, warthogs prefer to forage in dense, moist areas when available. The common warthog diet is omnivorous, composed of grasses, roots, berries and other fruits, bark, fungi, eggs, dead animals, and even small mammals, reptiles and birds. The diet is seasonably variable, depending on availability of different food items. Areas with many bulbs, rhizomes and nutritious roots can support large numbers of warthogs. Warthogs are powerful diggers, using both heads and feet. When feeding, they often bend the front legs backwards and move around staying on the knuckles. Although they can dig their own burrows, they commonly occupy abandoned burrows of aardvarks or other animals. The warthog commonly enters burrows "back-end first", with the head always facing the opening and ready to burst out as needed.Warthogs are fast runners and quite capable jumpers. They will often run with their tails in the air. Despite poor eyesight, warthogs have a good sense of smell, which they use for locating food, detecting predators and recognizing other animals.Although capable of fighting, with males aggressively fighting each other during mating season, a primary defence is to flee by means of fast sprinting. The main warthog predators are humans, lions, leopards, crocodiles, and hyenas. Cheetahs are also capable of catching small warthogs. However, if a female warthog has any piglets to defend she will defend them very aggressively. It has been reported that warthogs have given lions deep, serious, deadly wounds, which sometimes end with the lion bleeding to death.Warthogs have been observed allowing banded mongooses to groom them to remove ticks.