Werewolves can be easily distinguished from regular wolves by their shorter snout, more human-like eyes, the tufted tail, and their mindless hunting of humans whilst in wolf form.[3] At all other times, they appear as normal humans, although they will age prematurely, and will gain a pallor as the moon approaches and then wanes.

The real difference between a wolf and a werewolf is in behaviour. Genuine wolves are not very aggressive, and the vast number of folk tales representing them as mindless predators are now believed by wizarding authorities to refer to werewolves, not true wolves. A wolf is unlikely to attack a human except under exceptional circumstances. The werewolf, however, targets humans almost exclusively and poses very little danger to any other creature.