Which snake is the longest venomous snake?

The longest venomous snake is the king cobra. Its scientific name is Ophiophagus hannah, and exceptional individuals can reach more than 5 metres in length, making it longer than the black mamba and other commonly cited venomous snakes.

Despite its name and hood, the king cobra is not a true cobra in the genus Naja. It belongs to its own genus, Ophiophagus, a name meaning “snake-eater.” Its diet consists mainly of other snakes, including harmless species and venomous snakes, though it may also take lizards and small mammals.

King cobras are found across parts of the Indian subcontinent, Southeast Asia, and southern China. When threatened, they raise the front part of the body, spread a narrow hood, hiss, and may advance toward the perceived danger. Their venom is primarily neurotoxic, and their large size allows them to deliver a substantial quantity in a bite.

The king cobra is often confused with the black mamba, which is also long and highly venomous. The black mamba is generally regarded as the second-longest venomous snake, while the king cobra holds the length record.