Head and body length is 305-565 mm, the tail is 300-560 mm. Weights of adults range from 1,100 - 3,300 g. White markings on the face, throat and chest are characteristic of C. capucinus, coloration elsewhere ranges from yellowish gray to grayish brown. The tail is well haired and slightly prehensile, often slightly curled at the tip.

C. capucinus is arboreal and diurnal, being flexible in habitat choice. This species has been found in a variety of forest types and at elevations of 2,100 m. in the western Andes. In Costa Rica, C. capucinus has been found in nearly every type of forest as well as mangroves and sparsely forested areas. The diet is extremely varied and includes fruits, nuts, berries, seeds, flowers, buds, shoots, bark, gums, insects, arachnids, eggs, small vertebrates, and even some marine life including oysters and crabs.

In coastal areas where C. capucinus is not hunted or harassed, group size ranged from 20-30 individuals while in disturbed inland forests groups where much smaller and more leery of humans. Overall group sizes are between 6-50 monkeys. These consist of more females than males, but the groups seem to be dominated by a large older male. Usually one young is born after a gestation period of about 180 days. The baby immediately clings to its mother's fur with both hands and feet. If separated from its mother, other individuals in the troop will respond to its cries and give assistance. C. capucinus reaches full size and sexual maturity at 4 years for females and 8 years for males. Captive animals have been recorded to live to more than 46 years old.

C. capucinus is found from W Ecuador to Honduras.