The King Cobra (Ophiophagus hannah) is a species of venomous snake in the family Elapidae, endemic to forests from India through Southeast Asia. This serpent is the world's longest venomous snake and the largest of the elapids. The longest adult king cobras are 6 m (20 ft) long. Due to the size of its throat, the king cobra has the unique ability to growl rather than hiss. It is a cannibalistic snake, willing to eat even members of its own species. Despite the word "cobra" in its common name, this species does not belong to genus Naja, and is more closely related to mambas and taipans than to true cobras. It preys chiefly on other snakes and occasionally on some other vertebrates, such as lizards and rodents. It is a dangerous snake that has a fearsome reputation in its range, although it typically avoids confrontation with humans when possible. The king cobra is a prominent symbol in the mythology and folk traditions of Pakistan, India, Sri Lanka and Myanmar.
King cobras are unique among snakes in that the female creates a complex nest in which she lays her eggs. The nest has carefully engineered ventilation to assure temperature regulation within. The female will guard her nest zealously until right before the eggs are ready to hatch.
In 2024, Ophiophagus was taxonomically divided into four separate species: The Indian king cobra (O. hannah), the Sunda king cobra (O. bungarus), the Western Ghats king cobra (O. kaalinga) and the Luzon king cobra (O. salvatana).