The Florida softshell turtle typically has a dark brown to olive green, leathery carapace with a white or cream-colored underside, which visually conceals it from some predators. It has a long neck and an elongated head with a long snorkel-like nose. It is the largest soft-shell turtle in North America, reaching about 15–76 cm (5.9–30 in) in length. The female is larger, with the average male reaching only about 35 cm (14 in). The female can weigh up to 20 kg (44 lb), with the record weight documented at 43.5 kg. The juvenile is olive-yellow with grey spots and yellow lines. There are also yellow and orange markings on the head and the plastron is gray. The markings disappear or fade as it ages.
The turtle is almost entirely aquatic, only emerging from the water to bask or to lay eggs. It prefers the still waters of ponds, streams, lakes, and swamps. Like all soft-shells it is very fast-moving in water and on land. This species is carnivorous, consuming fish, insects, crustaceans, and molluscs. It may also scavenge.