25 Biggest Snakes in the World, Ranked by Length

The biggest snake in the world is large enough to eat a human being whole. Can you believe people keep some of these as pets?

Biggest Snakes in the World

If you don't like reptiles, the ball pythons at that reptile birthday party you went to as a kid probably seemed giant. The biggest snake in the world makes a ball python look like a dwarf hamster. Some species exceed 20 feet in length — roughly the length of a school bus.

We ranked the biggest snakes in the world by length. Weight is a whole other matter, but the top three snakes on this list easily outweigh a grown man. The really crazy part? Some people keep them as pets.

24. Green Tree Python (Tie)

Length: 6 feet

Weight: 5 pounds

Bottom Line: Green Tree Python

Morelia viridis / Chondrophyton viridis / Green Tree Python

Green tree pythons are the most classic looking snake we can think of. Kids usually color in snakes green, but most snake species are duller in color. Not the green tree python. Their vibrant coloration can be anything from aqua blue to bright yellow, with their adult color coming in by their first birthday.

Their green hue is no accident. They mostly live coiled up on tree branches, and their color helps them sneak up on prey unseen. Sometimes, they even use their tail as a lure, using it to attract curious rodents until they're close enough to catch.

24. Rainbow Boa (Tie)

close up of a rainbow snake head. Its can reflect sunlight into a rainbow.

Length: 6 feet

Weight: 5 pounds

Bottom Line: Rainbow Boa

Epicrates cenchria is a boa species endemic to Central and South America. Common names include the rainbow boa, and slender boa.

If you ever have a chance to handle a rainbow boa, do it. They have remarkably soft skin, and their scales act like prisms to create their signature rainbow effect in sunlight. They're considered medium-sized snakes, but a 6-foot snake would still be startling to run into in the woods.

They prefer living in humid forests in the Amazon River basin and the coastal regions of Venezuela. They're not big fans of climbing, however, preferring to hunt on the forest floor.

23. Emerald Tree Boa

Length: 6 feet

Weight: 6.5 pounds

Bottom Line: Emerald Tree Boa

Boa constrictor mythology whose function, or green tree Boa (LAT. Corallus caninus)

Emerald tree boas look almost exactly like green tree pythons. To the untrained eye, they're identical. But they're actually completely different species that come from totally different parts of the world.

The emerald tree boa lives in the canopy of the Amazon Rainforest, and it's an ambush hunter. It watches and waits from the trees above, and then strikes at rodents or birds wandering by on the forest floor. Emerald tree boas are live bearers, so they don't lay eggs. Instead, each baby is contained in a sack that ruptures before birth, allowing the baby snakes to emerge like mini versions of their parents.

22. Blood Python

Borneo short-tailed blood python snake Python curtus breitensteini

Length: 6 feet

Weight: 30 pounds

Bottom Line: Blood Python

Blood pythons aren't as popular as boa constrictors and ball pythons in the pet trade, but many keepers appreciate them for their large (but not too large) size. They have a wide variety of colors and patterns, and their irritable temperament is largely a myth.

Wild-caught specimens can be unpredictable, but that's true of all snakes. Those bred in captivity are only slightly tougher to handle than other popular snake species, and an experienced keeper can easily avoid bites by observing its body language.

20. Milk Snake (Tie)

Length: 7 feet

Weight: 3 pounds

Bottom Line: Milk Snake

Whether or not the milk snake deserves a spot on the list of biggest snakes in the world is up for debate. It all depends on how you define biggest. Milk snakes can grow up to 7 feet in length, but they're thin-bodied snakes that remain light and easy to handle. A 7-foot noodle is much less intimidating than a 7-foot fire hose!

Milk snakes are solitary and harmless, but most people steer clear of them because of their similar appearance to the venomous coral snake, which lives in the same region. They don't have an ounce of venom, but they like to pretend they do. When they're afraid, they make a vibrating sound like a rattlesnake and release a smelly fluid to deter predators.

20. Amazon Tree Boa (Tie)

Juvenile Amazon Tree Boa Snake on Branch

Length: 7 feet

Weight: 3 pounds

Bottom Line: Amazon Tree Boa

Amazon tree boas are commonly kept in the pet trade thanks to their wide range of vibrant colors. You can pick up an Amazon tree boa in shades of yellow, orange and gold, as long as you have the space for a 7-foot serpent in the house. They live all over South America and adapt well to changes in their environment. Even if people take over their territory, they adjust and find new ways to hunt. For example, they've adapted to living on plantations, catching rodents and bats when the humans are away.

True to their name, they prefer dwelling in trees and vegetation. They're fairly easy to keep in captivity, but they're feistier and more likely to strike defensively than other boa species.

19. Eastern Diamondback Rattler

Length: 7 feet

Weight: 34 pounds

Bottom Line: Eastern Diamondback Rattler

Eastern Diamondback Rattlesnake (Crotalus Adamanteus) — Eastern Diamondback rattlesnake.

The eastern diamondback rattlesnake isn't as mind-blowingly large as an anaconda, but it's plenty big enough to give unsuspecting hikers a scare. These rattlers live up to 20 years and continue growing throughout their lives. Most of them only weigh about 10 pounds, but the largest specimens can be three times as heavy and more than 7 feet long.

They're one of the largest snake species native to the U.S. as well as the longest and heaviest recorded rattlesnake species.

18. Dumeril's Boa

Length: 8 feet

Weight: 20 pounds

Bottom Line: Dumeril's Boa

The Dumeril's boa is a slow-growing beast of a snake. It takes at least five years to reach adulthood, but once it does, it's big. They average about 6 feet in length, but females of up to 10 feet have been reported.

They're native to the southwestern region of Madagascar, which is much drier than the habitats of most other boa species. In the wild, they're listed as vulnerable by the IUCN because of deforestation and human encroachment. Fortunately, they're easy to breed in captivity, so the unique species won't go extinct anytime soon.

17. Inland and Coastal Taipan

Taipan, one of the world’s deadliest snakes

Length: 8 feet

Weight: 22 pounds

Bottom Line: Inland and Coastal Taipan

Some of the "small" snakes on this list are the most lethal. Like most creatures that can kill you in minutes, taipans are native to Australia. There are two types, the inland and the coastal, but both are large and lethal. They're fast-moving and highly venomous. They're not aggressive unless they feel cornered, which is the only reason venturing into the Australian outback isn't completely insane.

It's still a solid 80 percent crazy, though, given the fact that, if you do get bit by a taipan, survival is unlikely. When they bite, they strike rapidly and repeatedly, delivering enough venom to kill an adult human in under an hour. Since they live in the remote wilderness, the odds of getting medical attention quickly enough are slim.

16. Eastern Indigo Snake

Length: 9 feet

Weight: 9 pounds

Bottom Line: Eastern Indigo Snake

Meet the longest snake in North America and the one you should be the least scared of. The eastern indigo snake is usually around 7 or 8 feet in length, and it's a fairly thin-bodied snake — much slimmer than the boa constrictors you see at the zoo. The largest recorded specimen was 9.2 feet long. That's a big snake, but big doesn't necessarily mean dangerous.

The matte-black eastern indigo snake is nonvenomous and safe to hold, and they're known to prey upon even more dangerous venomous snakes. They're federally protected, however, so you're unlikely to spot one at a reptile expo.

15. Southern White-Lipped Python

Length: 9 feet

Weight: 10 pounds

Bottom Line: Southern White-Lipped Python

Nearly black in color with a shimmering, iridescent sheen and striking white marks along its jaw, the white-lipped python is one of the most unique python species kept in the reptile hobby. There are actually seven different white-lipped python species, and the southern white lip is the largest.

Females tend to be larger than males, and some have topped 9 feet in length. They're not as common as many other large snake species, so you'll have to head to the island of New Guinea if you want to spot one in the wild.

14. King Brown Snake

Length: 11 feet

Weight: 13 pounds

Bottom Line: King Brown Snake

Oh, look. Another venomous nope rope from Australia. Big shocker. The king brown snake is native to Central Australia, and we'd rather take a bite from a Burmese python than one of these.

They're not very heavy, but their thin, agile body is built for striking at lightning speed. They usually reach 8 to 11 feet in length and deliver around 180 milligrams of venom per bite. Remind us why anyone lives in Australia?

13. Yellow Anaconda

Length: 11 feet

Weight: 80 pounds

Bottom Line: Yellow Anaconda

Any animal with the name "anaconda" is bound to be big. Anacondas are cousins of boa constrictors, but even species that look very similar can vary drastically in size. The yellow anaconda is smaller than the green anaconda and usually weighs between 55 and 80 pounds full-grown.

These giant constrictors are native to South America, living primarily in the wetlands. They're nonvenomous, opportunistic feeders, so they'll snack on whatever they can find in the wild. Small mammals, birds, frogs, fish and eggs are their top choices, but they've been known to resort to cannibalism from time to time.

12. Coastal Carpet Python

Length: 12 feet

Weight: 30 pounds

Bottom Line: Coastal Carpet Python

The coastal carpet python is a heavy-bodied snake with a distinctive blotchy pattern. They live throughout the Greater Brisbane region in Australia, and it's not uncommon for them to sneak into houses or sheds. They're one of the most commonly encountered snakes in the area, in part because they're active around the clock, not just at night.

These big snakes mostly eat rodents and smaller reptiles, but adult specimens have been known to snack on guinea pigs, cats and even dogs.

11. Bushmaster

Venomous Bushmaster Snake (Lachesis muta) in Rainforest

Length: 13 feet

Weight: 11 pounds

Bottom Line: Bushmaster

Black Headed Bushmaster (Lachesis melanocephala) with forked tongue

Pythons and boas are puppy dogs in comparison to the bushmaster. You'd rather run into a much larger python than one of these. Bushmaster snakes are native to South America, and they have one of the deadliest bites in the world.

Bushmasters have so much venom that mortality rates after a bite aren't great even with medical treatment. Luckily, these large pit vipers are solitary and shy, and rarely bite unless they're confronted. It's the largest venomous snake in all of the western hemisphere. Interestingly, it's only 15 inches long when it's born, and mother bushmasters are one of the few snakes that guard eggs until they hatch.

10. Papuan Olive Python

Length: 13 feet

Weight: 50 pounds

Bottom Line: Papuan Olive Python

The Papuan olive python, also known as the Apodora, is a thick, stocky python species that can only be found in the dense forests of Papua New Guinea. Spotting a Papuan olive python is unlikely since they're a solitary, lesser-known species, but they easily earn a spot on the list of biggest snakes in the world.

They can weigh as much as a toddler and are about the length of a midsize sedan. Luckily, they're not aggressive toward humans and would rather slither away quietly than confront trespassers.

9. Boa Constrictor

Length: 13 feet

Weight: 60 pounds

Bottom Line: Boa Constrictor

Boa constrictors are likely one of the more recognizable names on this list. They're commonly kept as pets, but that isn't as crazy as it sounds. Boas are big and heavy, but they're nonvenomous, and their stats are deceptive. Firstly, there are two species of boa constrictor: boa constrictor (also known as the red-tailed boa) and boa imperator. The two species look similar, but true red-tailed boas are much larger. The smaller boa imperator rarely tops 8 feet, and some localities never grow over 4 or 5 feet.

Interestingly, boas tend to grow larger in captivity than in the wild, and females are almost always larger than males.

8. Black Mamba

Length: 14 feet

Weight: 5 pounds

Bottom Line: Black Mamba

Selective focus shot of a black mamba snake reptile — A selective focus shot of a black mamba snake reptile

The black mamba is like the most deadly piece of burnt spaghetti you could possibly encounter. They're darkest in color as babies, fading to a silvery grey color with age. A 14-foot black mamba is rare, but adults often reach 9 feet. Even if a black mamba is smaller than a boa, you'd much rather pick up a 13-foot boa than a 7-foot black mamba. Victims of a black mamba bite lose the ability to speak after about 20 minutes. In an hour, they're unconscious. By six hours post-bite, they're goners without an antidote.

That said, the reports of black mambas aggressively chasing people don't tell the whole story. Black mambas would prefer to avoid confrontation. Cases of supposed pursuit were likely examples of a person accidentally blocking a black mamba's path to its burrow.

7. Amethystine Python

Length: 18 feet

Weight: 53 pounds

Bottom Line: Amethystine Python

Scrub python known as Morelia amethistina

The amethystine python, also known as the scrub python, is a nonvenomous snake found in Australia, Papua New Guinea and Indonesia. Scrub pythons are the longest species of snake native to Australia, but their dietary habits aren't particularly scary. They mostly eat rats, possums, fruit bats and occasionally lizards. While some reports of scrub pythons over 25 feet have popped up over the years, most never exceed 18 feet.

Keep in mind that length isn't everything. While an 18-foot snake is intimidating, snakes can only eat prey that they can swallow whole. Scrub python mouths aren't nearly large enough to take on a human, and they know it. Any attacks on humans are likely defensive, not predatory.

6. Central African Rock Python

The Southern African rock python (Python natalensis)

Length: 18 feet

Weight: 120 pounds

Bottom Line: Central African Rock Python

Python sebae, commonly known as the Central African rock python, is a large, nonvenomous snake of Sub-Saharan Africa. Masai Mara National Reserve, Kenya.

The African rock python has a reputation for being aggressive, and it's not completely undeserved. While some herpetologists keep them as pets, most reptile keepers wouldn't touch an African rock python with a 10-foot pole. Their exceptional size and unpleasant temperament make them more dangerous to interact with than some of the even larger species on this list.

Any snake over 8 feet should be handled with caution, but an African rock python probably shouldn't be handled at all. It has few natural predators, so the only threat to the species is habitat loss.

5. King Cobra

Length: 19 feet

Weight: 45 pounds

Bottom Line: King Cobra

A 45-pound snake isn't the hardest to overpower, but that's if you don't consider the murder weapon lurking at one end. King cobras are the longest venomous snakes in the world, although their average length is closer to 12 feet than 20. They're slim-bodied snakes, but they rear up and flare out a defensive hood to look more intimidating. No need, cobra. We weren't going to get in your way.

They're only found in southern and southeast Asia, but some specimens can be seen in captivity. Curious what handling a king cobra is like? It's been done and with an albino version, too.

4. Indian Rock Python

Length: 20 feet

Weight: 200 pounds

Bottom Line: Indian Rock Python

Python Molurus Molurus. Indian Rock python. Non venomous. Captive specimen. Maharashtra, India.

Are you noticing a theme? Both boas and pythons are large constrictors, and most species that fall into these two categories are large. The Indian rock python lives in India (fitting), plus Pakistan, Nepal, Bangladesh, Sri Lanka and Bhutan.

They usually don't grow over about 10 feet, but they'll occasionally reach double-digit lengths if given enough time and available prey.

3. Burmese Python

Length: 27 feet

Weight: 215 pounds

Bottom Line: Burmese Python

The Burmese python is pretty much tied with the reticulated python (up next) in size. The Burmese python tends to be thicker and shorter, while the reticulated python is longer and more slender. Both are giants, and both are popularly kept by serious reptile keepers.

Burmese pythons are about as friendly and safe to handle as a 15 feet (or longer) snake can get, but their size is nothing to scoff at. Snakes that large require at least two people to handle, and they need a zoo-sized enclosure to house them. Unfortunately, many people don't realize just how big a Burmese python will get before they pick one up. In fact, enough people released them into the wild that the Florida Everglades are now overrun with invasive Burmese pythons.

2. Reticulated Python

Length: 32 feet

Weight: 200 pounds

Bottom Line: Reticulated Python

The reticulated python goes down in the record books as the largest snake kept in captivity. Medusa, a 25-foot, 2-inch giant, weighed 350 pounds when she was just 8 years old. She currently holds the record for the largest reticulated python in captivity, edging out the previous record holder at Ohio's Columbus Zoo. That one's name is Fluffy.

For such a giant snake, she's surprisingly easy to handle. Reticulated pythons aren't aggressive snakes; they're just giant. As with any giant animal, accidents can happen, so hopping into the snake enclosure at the zoo is still a bad idea. Luckily, hobbyists have been selectively breeding dwarf and super-dwarf retics that have all the beauty of a full-sized one in a much more manageable size.

1. Green Anaconda

Length: 33 feet

Weight: 550 pounds

Bottom Line: Green Anaconda

Retics, Burms and green anacondas are all giants, but the latter of the three takes the cake for the biggest snake in the world. A type of boa, the green anaconda is huge, brutally strong and loves to swim. They live in tropical habitats throughout South America, and can easily top 25 feet in length. The largest recorded specimen hit 33 feet.

Remember how we said that most giant snakes are too slim to pose a serious threat to humans? That doesn't apply here. Green anacondas have been known to take on gators, and it's technically possible for them to eat a human being. We'll stay out of the rainforest, just in case.

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