Black hawk-eagles are mostly black in colour, but have a variety of patterns on the body and wings (white spots and bars). A white line can be seen just above each eye. The black feathers of the crest have white bases. The undertail and underwings have narrow, white bars. They have broad, short wings and a long, rounded tail. The long, narrow tail has distinctive grey bands with a brownish grey tip and is rarely fanned. The eyes are orange and the feet are yellow with black talons. Juveniles are quite different in appearance, almost the reverse of the adult colouration, being largely off-white with black streaking and mottling.