Adélie penguin colonies are found on ice-free coastal areas of the Antarctic continent and several nearby islands (e.g. S. Shetland, S. Orkney, S. Sandwich, Balleny and Peter Islands). These penguins are mid-sized, being 46 to 71 cm (18 to 28 in) in height and 3.6 to 6 kg (7.9 to 13.2 lb) in weight. Distinctive marks are the white ring surrounding the eye and the feathers at the base of the bill. These long feathers hide most of the red bill. The tail is a little longer than other penguins’ tails. The appearance looks somewhat like a tuxedo. They are a little smaller than other penguin species. Their appearance is closest to the stereotypical image of penguins as mostly black with a white belly.

Adélie penguins usually swim at around 5 miles per hour (8.0 km/h).