This giant among all North American frogs often attains a length of 15 cm (6 in.) or more.

Bullfrogs inhabit lakes, rivers, and large ponds from southern Nova Scotia to southern Ontario. In North America, this plain or nearly plain green frog is found through Nova Scotia to central Florida; west to Wisconsin and across the Great Plains to the Rockies. It has also been widely introduced in the rest of the world.

Breeding occurs from late May to early July in the northern hemisphere, and February to October in the southern hemisphere. This is when you will hear the call of the males on warm evenings, a vibrant, low frequency "jug-o-rum" or "oua-oua-ron" which can be heard over a distance of 1 km (3,280 ft.).

Bullfrogs are collected for dissection in educational courses, and their meaty hind legs are found on menus in some regions.