The Woolly-necked Stork is a medium-sized stork standing 75–92 cm tall. It has deep crimson or wine-red irises and a shiny black body overall, accented by a black “skull cap” and a downy white neck, which is the source of its name. Its lower belly and under-tail coverts are white, creating a striking contrast with the dark plumage. The feathers on the fore-neck have a coppery-purple iridescence and can be raised during displays. The tail is deeply forked and white, generally concealed by long black under-tail coverts. The stork has long red legs and a heavy blackish bill, though some individuals have bills that are mostly dark red with only the base third being black. Both sexes look alike, though males are believed to be slightly larger. Juveniles are duller in color, with a feathered, occasionally black-and-white streaked forehead. In Africa, the black cap on the Woolly-necked Stork has a diffuse or jagged edge, unlike the sharp, clean border seen in Asian birds. When the wings are spread, either during displays or in flight, a narrow band of very bright, unfeathered skin is visible along the underside of the forearm, described as “neon orange-red,” “like a red-gold jewel,” or “almost glowing” up close. Young nestlings are pale grey with buffy down on the neck and a black crown. By fledging age, immature birds closely resemble adults but have a feathered forehead, less iridescence in their feathers, and longer, fluffier neck feathers.