Capybaras are the largest of rodents, weighing from 35 to 66 kg and standing up to 0.6 meters at the shoulder, with a length of about 1.2 meters. Females of this species are slightly larger than males. Their fur is coarse and thin, and is reddish brown over most of the body, turning yellowish brown on the belly and sometimes black on the face. The body is barrel-shaped, sturdy, and tailless. The front legs are slightly shorter than the hind legs, and the feet are partially webbed. This, in addition to the location of the eyes, ears, and nostrils on top of the head, make capybaras well-suited to semi-aquatic life.

Range mass: 35 to 66 kg.

Range length: 106 to 134 cm.

Other Physical Features: endothermic ; homoiothermic; bilateral symmetry

Sexual Dimorphism: female larger