Bell's hinge-back tortoise is a medium-sized light brown tortoise. They can grow up to 22 cm. On the back of its shell, the tortoise has a 90 degree hinge which, when closed, can protect its rear legs and tail from predators. This broad band of flexible connective tissue is located between the 4th and 5th costals and the 7th and 8th peripherals in adults.
The scutes on its slightly domed and elongated shell typically have a radiating pattern of dark patches, though these can fade. Adult males have a concave belly. Most Bell's hinge-backs have five claws on each forefoot except for one of the subspecies, K. b. nogeuyi.