Pteranodon is part of the family Pteranodontidae, part of the clade Pteranodontia, which also includes nyctosaurids. Pteranodontians form a larger clade, Pteranodontoidea, alongside ornithocheiromorphs, and that clade falls under the suborder Pterodactyloidea. While not dinosaurs, pterosaurs such as Pteranodon form a clade closely related to dinosaurs as both fall within the clade Avemetatarsalia. Male and female Pteranodon differed in size and crest shape. Males attained wingspans of 5.6–7.6 m (18–25 ft); females were smaller, averaging 3.8 m (12 ft). The crests of males were far larger than those of females. In P. longiceps, they were long and backswept, whereas in P. sternbergi, they were tall and upright. Females also had wider pelvises than males.
