Mules draw different anatomic, physiologic, and temperamental characteristics from each of their parents. A mule resembles a horse in its height, the length and shape of its neck, and the length of its coat and tail bone. It resembles a donkey in its short thick head, long ears, short mane, coarse coat texture, thin limbs, and small hooves. The hair on the first half of the tail is short like a donkey's and it is long on the second half, but not as long as a horse's. Mules come in all horse colors, including leopard, appaloosa, and pinto, but their belly hair is usually lighter and finer like a donkey's.
Mules can bray like donkeys or whinny like horses.
A mule's foot is more elastic, upright, and boxlike than a horse's. A healthy mule foot on a horse would appear to be a very contracted foot. A mule's hoof is more supple and less likely to chop than a horse's. Some mule hooves grow continuously, without wearing down or chipping, which can be crippling if not trimmed. Mules require the same vaccinations and parasite control as horses.