Two-toed vs three-toed sloth: the key differences
The word "sloth" covers six living species in two quite different groups: the three-toed sloths (genus Bradypus, four species) and the two-toed sloths (genus Choloepus, two species). They share the famous slow lifestyle but differ in their claws, what they eat, when they are active and how threatened they are. Our sloth species guide covers the whole family; this comparison zooms in on the two groups people most often mix up.
Count the front claws, not the toes
The names are misleading. Every sloth, in both groups, has three toes on its hind feet. The difference is on the forelimbs: three-toed sloths have three claws on each front limb, while two-toed sloths have two. That front-claw count is the single most reliable way to tell the groups apart, since both can look similar at a glance in the canopy.
Diet and daily rhythm
Three-toed sloths are almost pure leaf-eaters, browsing a narrow range of foliage. Two-toed sloths are more omnivorous, adding fruit and, occasionally, small animals to their leaves. Their daily clocks differ too: three-toed sloths are mainly active by day, whereas two-toed sloths are largely nocturnal, which is one reason the two-toed species are seen less often by visitors. Two-toed sloths also tend to be a little larger and heavier, generally around 4 to 9 kg against roughly 3.5 to 6 kg for three-toed sloths.
Reproduction and lifespan
Gestation is markedly longer in two-toed sloths, at about 10 to 12 months, compared with roughly 6 months in three-toed sloths; both usually raise a single cub at a time. Two-toed sloths also tend to do better in human care, where some have lived into their 30s and 40s, with one recorded near 50.
Conservation: where the real difference lies
Most sloths are still widespread. Both two-toed species are currently Least Concern. Among the three-toed sloths the picture is more mixed and includes the family's most threatened members: the maned sloth of Brazil's Atlantic Forest is Endangered, and the pygmy three-toed sloth, found on a single small island off Panama, is Critically Endangered with only a few hundred to a few thousand individuals. Across both groups, habitat loss, the illegal pet trade, road traffic and power-line electrocution are the recurring threats, especially in fragmented forest in countries such as Brazil and Colombia. Partner-funded shelters there rescue sloths of both kinds, and you can help quietly through our donation page.
Read the full Sloth wildlife guide for the facts, IUCN status and conservation context — or donate to WARN to help fund the local partners protecting this species.
