Ranidae, family of wide-ranging frogs of the order Anura, containing several genera and more than 600 species. Representatives occur on every continent except Antarctica. Members of this group are referred to as the true frogs. Although most are aquatic or semiaquatic, a few ranids are ground burrowers or arboreal. Some species are live-bearers.
The eggs of most species are laid in water and develop into typical tadpoles prior to metamorphosis. The most common genus is Rana, which includes the large bullfrog of North America. See also bullfrog; common frog; green frog; leopard frog; marsh frog; pickerel frog; wood frog.