Cuculus canorus is approximately 33 cm in length. Adult males are generally gray above, including the throat and breast, while the underparts are white with close black bars. The tail, which is long and graduated, is black with white spots. The cuckoo has short legs and a non-hooked bill. A noticeable feature of C. canorus is that it has very pointed wings. The adult females are occasionally brown above, white below, and barred black. The juvenile cuckoos resemble the rare brown phase of the female. Juveniles are brown, barred, and have a white patch on the back of the neck. The voicing of C. canorus differs between males and females. The males have an unmistakable coocoo call, while the females have a babbling call. (Hammond and Everett 1980; Heinzel and Fitter 1972; Bruun 1970)
Average mass: 111.6 g.
Average basal metabolic rate: 0.838 W.