The underbelly is light-colored with a pattern of irregular dark streaks along the wingspan and vertically across the breast and legs.
Males tend to have a slightly lighter breast.
The large black eyes are generally surrounded by a yellow eye ring and the beak and feet are bright yellow. Like all raptors, peregrines have a sharp hooked beak for tearing food. Falcons, including peregrines, also have a notch in the upper beak that is used in killing prey by severing the spinal cord. Peregrines range from about 15 to 20 inches and female peregrines are larger and stronger than the males. Peregrines are the fastest animal on earth.