The dwarf sperm whale has a robust and stocky body, but smaller than that of the pygmy sperm whale. Its morphology is similar, with a compact body, long and narrow at the posterior level, but its head is more pointed and its muzzle shorter. Another distinctive character is its dorsal fin: located in the center of the back, it is prominent, with a broad base and a pointed end. Its back has a dark bluish-grey tint, while its sides are lighter and its belly is white.