The average polar bear is much larger than the average brown bear. Polar bears are considered the largest living carnivores on land, and large males often weigh more than a thousand pounds. Grizzly bears are actually a kind of brown bear; the two are not distinct.
Most polar bears weigh between 300 and 1,700 pounds, with females being much smaller on average than males. Brown bears average between 180 and 1,300 pounds, again with females being smaller. The average size for male brown bears is less than a thousand pounds. However, Kodiak bears, a subspecies of brown bear, can sometimes exceed 2,000 pounds.
The heaviest brown bear ever recorded as of 2015 was a Kodiak bear named Clyde. He weighed 2,130 pounds when he died in 1987. However, he is not the largest bear ever recorded. The largest bear as of 2015 was a wild male polar bear shot in 1960; he weighed 2,210 pounds. Reports of brown bears exceeding 2,400 or even 2,550 pounds have not been substantiated.