Very big! Adult males normally weigh 350 to more than 650 kg. Adult females are smaller, normally weighing 150 to 350 kg.
Researchers in Canada estimated one male bear at 800 kg! cientists usually refer to how tall bears are by measuring them at the shoulder when on all fours. Those heights are typically 1-1.5 meters for adult polar bears. An adult male may reach over three meters when standing on its hind legs.
