The white-tailed deer's coat is a reddish-brown in the spring and summer, and turns to a grey-brown throughout the fall and winter. The white-tailed deer can be recognized by the characteristic white underside to its tail. It raises its tail when it is alarmed to warn the predator that it has been detected. North American male deer (also known as a buck) usually weigh 150 to 300 lb, but mature bucks over 400 lb have been recorded. Males regrow their antlers every year. About one in 10,000 females also has antlers, although this is usually associated with freemartinism. Bucks without branching antlers are often termed "spikehorn", "spiked bucks", "spike bucks", or simply "spikes/spikers.

White-tailed deer are generalists and can adapt to a wide variety of habitats. Although most often thought of as forest animals depending on relatively small openings and edges, white-tailed deer can equally adapt themselves to life in more open prairie, savanna woodlands, and sage communities as in the Southwestern United States and northern Mexico. There are several natural predators of white-tailed deer, with wolves, cougars, American alligators, jaguars (in the American southwest, Mexico, and Central and South America) and humans being the most effective natural predators. Aside from humans, these predators frequently pick out easily caught young or infirm deer.