The largest living snakes in the world, measured either by length or by weight, are various members of the Boidae and Pythonidae families.
They include anacondas, pythons and boa constrictors, which are all non-venomous constrictors.
The longest venomous snake, with a length up to 18.5–18.8 ft (5.6–5.7 m), is the king cobra,[1] and the heaviest venomous snake is likely to be the Gaboon viper (which also has the longest fangs and delivers the largest amount of venom) or possibly the Eastern diamondback rattlesnake – all three of these reach maximum weights in the range of 6–20 kilograms (13–44 lb).