The black bulbul is 24-25 cm in length, with a long tail. The body plumage ranges from slate grey to shimmering black, depending on the race. The beak, legs, and feet are all red and the head has a black fluffy crest. Sexes are similar in plumage, but young birds lack the crest, have whitish underparts with a grey breast band, and have a brown tint to the upperparts. They have a black streak behind the eye and on the ear coverts.