Top 10: Biggest snakes in the world

Measuring and listing the biggest snakes in the world is no mean feat. Aside from the obvious dangers involved in approaching a snake with a tape measure, snakes do not tend to stay still in a completely straight line very often. So if you want to measure a snake (though we would not advise you to try!), it is best that they are heavily sedated before you start.

We have brought together some of the world's largest snakes, in terms of length at least, and sorted them into a handy top 10.

A lot of factors can affect the weight and size of snakes, so to keep things relatively accurate, our list comprises measurements taken from wild individuals (as captive snakes tend to be heavier and grow longer due to easy access to food).

Finally, because of the unreliability of the data out there, this list should be taken with a pinch of salt.

10. King brown - Pseudechis australis

Also known as the mulga snake, the king brown is a highly venomous species, native to large parts of Australia. It has been recorded at lengths of up to 3.3m in the wild. While not as dangerous as some of Australia's other snake species, its venom can cause blood clots and muscle damage if administered to humans in large enough quantities.

9. Boa constrictor - Boa constrictor

Boas are non-venomous constrictor snakes, usually found in the tropical habitats of South America. They have a large variation in colours and patterns to help them blend in to their surroundings. On average, they have been known to grow up to 4m in the wild, with females generally being larger than males overall.

8. Black mamba - Dendroaspis polylepis

Equally at home on the ground or in the trees, the black mamba is one of the most formidable snakes in the world. While on average they only tend to grow to 3m, some adults have been known to reach 4.3 to 4.5 m in the wild. When threatened, this snake can attack from quite a distance, travelling at 16km/h and delivering a rapid succession of bites from its ultra-sharp fangs.

7. Indian python - Python molurus

Perhaps best known as Kaa in Rudyard Kipling's 'The Jungle Book' (and the Disney film of the same name), the Indian python is non-venomous, and is also quite slow-moving and ponderous. The longest recorded specimen was found in Pakistan, measuring 4.6m in length, and a hefty 52kg in weight.

6. King cobra - Ophiophagus hannah

The king cobra is the longest venomous snake on our list, with an average length of 3.2 to 4m, with one individual recorded at 5.85m in the wild. They tend to prey on other snakes, including other king cobras, but are capable of delivering a fatal dose of neurotoxic venom to a human if threatened.

5. African rock python - Python sebae

Africa's biggest snake species and a member of the constrictor group, the African rock python is fearsome, and has been known to eat the occasional monkey or crocodile. Growing up to 6m in length in the wild, they certainly have the stomach for it. They are also known for the distinctive triangular shape below their eyes, and their rows of sharp teeth.

4. Burmese python - Python bivittatus

The stunning Burmese python can grow up to 5m in length, while the official record holder is a snake named 'Baby', who reached a length of 5.74m. However, this pales in comparison to an individual that was estimated to be 8.2m, although this sighting - and indeed the measurement - is unofficial. Sadly, due to the illegal pet trade, this snake is now considered to be an invasive species in Florida, USA.

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3. Amethystine python - Morelia amethistina

Also known as the scrub python, this snake is native to Indonesia, Australia and Papua New Guinea. They have been noted to prey on wallabies and small rodents by hiding near water sources, and are also noted for being good swimmers. In the wild they average around 5m, like this internet sensation. However, it is thought that they can grow to over 8.5m.

2. Reticulated python - Python reticulatus

The longest-ever snake recorded in captivity was a reticulated python that reached 10m in length. In the wild, these snakes tend to be smaller, with an individual measuring 8m captured in 2016 on a construction site in Malaysia. Reticulated means a grid or network, and refers to the patterns on the skin of the snake, which is highly distinctive.

1. Green anaconda - Eunectes murinus

The green anaconda is usually found in South America, and is a member of the boa family, which means it is not venomous, but uses constriction to kill its prey. With an average weight of up to 80kg, it probably doesn't have to wait too long until its lunch is ready. It is thought to be the heaviest snake species in the world, and also one of the longest at up to 9m. Locating and measuring the species is tricky because of the remoteness of their habitat, with unconfirmed reports of individuals reaching over a whopping 11m.