Pangolin species vary in size from about 1.6kg (~3.5 lbs) to a maximum of about 33kg (~73 lbs). They vary in color from light to yellowish brown through olive to dark brown. Protective, overlapping scales cover most of their bodies. These scales are made from keratin — the same protein that forms human hair and fingernails. Overlapping like artichoke leaves, the scales grow throughout the life of a pangolin just like hair; scale edges are constantly filed down as pangolins dig burrows and tunnel through the soil in search of termites and ants. Pangolin undersides do not have scales, and are covered with sparse fur. The four Asian pangolins are distinguished from the African species by the presence of bristles which emerge from between the scales.

With small conical heads and jaws lacking teeth, pangolins have amazingly long, muscular, and sticky tongues that are perfect for reaching and lapping up ants and termites in deep cavities. Pangolins have poor vision, so they locate termite and ant nests with their strong sense of smell. A pangolin's tongue is attached near its pelvis and last pair of ribs, and when fully extended can be up to half the length of the animal's head and body. A pangolin’s stomach is muscular and has keratinous spines projecting into its interior. Usually containing small stones, the stomach mashes and grinds prey in much the same manner as a bird’s gizzard.

Pangolin limbs are stout and well adapted for digging. Each paw has five toes, and their forefeet have three long, curved, claws used to demolish the nests of termites and ants and to dig nesting and sleeping burrows. Pangolins shuffle on all four limbs, balancing on the outer edges of their forefeet and tucking their foreclaws underneath as they walk. They can run surprisingly fast, and will often rise on their hind limbs to sniff the air. Pangolins are also capable swimmers, and while some pangolin species such as the ground pangolin (Smutsia temmincki) are completely terrestrial, others, such as the black-bellied pangolin (Phataginus tetradactyla), are adept climbers, using their claws and semi-prehensile tails to grip bark and scale trees.