Which sea turtle species is the largest living turtle?

The leatherback sea turtle is the largest living turtle. It can reach about 2.7 meters in length and weigh roughly 500 kilograms, making it the heaviest living non-crocodilian reptile as well.

Its scientific name is Dermochelys coriacea, and it is the only living species in its family, Dermochelyidae. Unlike other living sea turtles, it lacks a rigid, bony shell covered by large scutes. Instead, its back is formed by a flexible layer of leathery skin containing tiny bony structures, which gives the species its name.

Leatherbacks are built for long-distance ocean travel. Their large front flippers, streamlined bodies, and special adaptations for retaining body heat allow them to cross cold waters and range across most of the world's oceans. They mainly eat jellyfish and other soft-bodied prey. A common mix-up is confusing the leatherback with the green turtle: green turtles are often larger-looking than other hard-shelled sea turtles, but the leatherback is the overall size champion. Fossil species such as Archelon were larger, but they are extinct.