The adult magpie ranges from in length with a wingspan, and weighing . Its robust wedge-shaped bill is bluish-white bordered with black, with a small hook at the tip. The black legs are long and strong. The plumage is pure glossy black and white; both sexes of all subspecies have black heads, wings and underparts with white shoulders. The tail has a black terminal band. The nape is white in the male and light greyish-white in the female. Mature magpies have dull red eyes, in contrast to the yellow eyes of currawongs and white eyes of Australian ravens and crows. The main difference between the subspecies lies in the "saddle" markings on the back below the nape. Black-backed subspecies have a black saddle and white nape. White-backed subspecies have a wholly white nape and saddle. The male Western Australian subspecies "dorsalis" is also white-backed, but the equivalent area in the female is scalloped black.