The banteng is similar in size to domestic cattle, measuring 1.55 to 1.65 m (5 ft 1 in to 5 ft 5 in) tall at the shoulder and 2.45??.5 m (8 ft 0 in??1 ft 6 in) in total length, including a 60 cm (2.0 ft) tail. Body weight can range from 400 to 900 kg (880 to 1,980 lb).

Banteng exhibit sexual dimorphism, allowing the sexes to be readily distinguished by colour and size. In mature males, the short-haired coat is blue-black or dark chestnut in colour, while in females and young it is chestnut with a dark dorsal stripe. Both males and females have white stockings on their lower legs, a white rump, a white muzzle, and white spots above the eyes.