The eastern cottontail is a medium-sized rabbit with long ears, large hind legs, shorter front legs, a short fluffy tail, and soft fur. The upperparts vary from reddish to grayish brown sprinkled with black; when fluffed, the fur of the rump is grayish. The back of the neck is bright rust-colored. The underparts are grayish white except for a brownish chest; the tops of the hind feet are tan to whitish. Rabbits feed almost entirely on plants and also certain sedges, forbs, and cultivated plants. To survive during heavy snow cover, they eat buds, twigs, bark, and sprouts of shrubs, vines, and trees.

Eastern cottontails inhabited a variety of habitat types, including deserts, swamps, and forests. They are now most often found in meadows, orchards, farmlands, bushes and areas with low bushes, vines and low deciduous trees. When an eastern cottontail faces a predator—which include hawks, owls, foxes, snakes, and even dogs and cats—it uses its speed to keep it safe, sometimes hopping up to 18 miles an hour. All the zigging and zagging they do makes it harder for other animals to catch them. Their excellent sense of smell helps them stay safe too. They have about 100 million scent receptors in their noses, which they twitch to expose as many of the scent receptors as possible to sniff out danger.