How big does an orangutan get?
Orangutans are the largest animals that live primarily in trees, and the difference between the sexes is dramatic. Adult males reach roughly 90 kg in the wild, and considerably more in captivity, while females typically weigh about 37 to 50 kg — close to half a male's size. Standing height is around 1.2 to 1.4 metres, but the headline figure is the reach: a big male's arm span can stretch to about 2 metres from fingertip to fingertip, longer than he is tall. Our orangutan species guide sets out the full measurements.
How strong is an orangutan?
An orangutan's body is engineered for hanging, hauling and climbing. Long, hook-like hands, mobile shoulder joints and dense arm muscle let an adult support its whole weight from a single branch and move deliberately through the canopy. That same build gives them considerable pulling strength relative to their size — strength they use for foraging and travel rather than aggression, since orangutans are generally slow-moving and not confrontational by nature.
What are the cheek pads on male orangutans?
The broad facial discs on dominant males are called flanges. They are pads of fibrous and fatty tissue whose growth is driven by testosterone, and only fully mature, dominant males develop them. Flanges make a male look larger and, together with his throat sac, help project the booming "long call" — a roar that can carry across roughly a mile of forest to attract females and keep rival males at a distance. Remarkably, some males stay unflanged for years and can develop the pads later if they rise in status.
How does their size compare with other great apes?
Orangutans are heavier than most chimpanzees but far lighter than gorillas, whose silverback males can exceed 200 kg. What sets orangutans apart is not raw mass but proportion: no other great ape combines this body size with such a sweeping arm span and such a fully arboreal lifestyle.
Why their build matters for survival
That specialised body ties orangutans tightly to tall, connected forest. When canopy is fragmented by clearance, these heavy climbers are forced to the ground and into danger. Our rehabilitation partners help displaced and orphaned orangutans relearn canopy life before release; you can help fund that work if you would like to.
Read the full Orangutan wildlife guide for the facts, IUCN status and conservation context — or donate to WARN to help fund the local partners protecting this species.
