Article: The World’s Most Venomous Snakes: HowStuffWorks
The World’s Most Venomous Snakes
About This Article
There are a few thousand species of snakes in the world, and upward of 600 of them possess venom. That's not to say 600 species of snakes in the world are dangerously deadly; the common garter snake was recently determined to have very mild venom and those things live all over North America in people's gardens. It's the snakes with the serious venom you need to worry about, the kinds that produce enough toxin to kill multiple healthy adults. Those snakes are the ones that people fear, but they're also ones that are often least understood. They're just animals, after all, and their venom is just the way by which they defend themselves from predators or incapacitate their prey so they can survive. It's just when human and snakes cross paths that things get ugly.
If you have an interest in snakes, either a fear of the dangerous ones or a respect for the rare and deadliest kind, then it never hurts to learn a little more about them. Snakes often just want to be left alone and they will enforce that desire in a very serious and painful way sometimes. We've assembled a list of 25 of the most venomous that should definitely be avoided. Slither on in and see!
It has a rattle, but it's no baby!
The eastern diamondback rattlesnake is the largest of the rattlers you'll find in North America, which means you probably never actually want to find one of these. The largest one on record was nearly 8 feet long and they tend to be heavier than most snakes as well. Its fangs are nearly an inch long and while it spends most of its time eating rabbits, it will strike at a human when provoked. Like all rattlesnakes, it does have that warning rattle but it's worth noting it doesn't always use it.
The most venomous cobra
Of all the cobra species, the Caspian cobra is the most venomous. Naturally, there's anti-venom available for you if you get bitten, but the downside of that is it's not nearly as effective as you'd hope. Massive doses will need to be administered and it needs to be administered pretty quickly as well. The venom of this snake is so potent it's been known to kill in about an hour.
The most dangerous sea snake
Either as a result of being so commonplace and wide-ranging around the world from the Persian Gulf to Southeast Asia or because it's just a surly creature, the beaked sea snake is believed to be responsible for about 50% to 90% of all sea snake bites in the world. As a result of that, it's also to blame for most sea snake fatalities in the world. It's best to be avoided at all costs.
Avoid the inland taipan.
If there's one snake to avoid more than any other snake in the entire world, it's the inland taipan. This is the most toxic snake out there and, worse than that, it's actually evolved to be more deadly to mammals. Its venom is adapted to specifically be effective against warm-blooded animals. One single bite from an inland taipan is estimated to have about enough venom to kill 100 adult men. Death can occur in as little as 30 minutes after being bitten.
A reason to be wary in the desert
Arguably the deadliest snake in North America, the Mojave rattler has the most potent venom of any rattlesnake out there. Luckily there's a really good chance of survival for anyone who seeks treatment quickly for a bite, but that speed is the key. These snakes are so dangerous there are even stories of people pricking their fingers on the fangs of dead ones and becoming envenomated.
This not-so-little guy is the South American bushmaster and it's the longest pit viper in the world. Some can reach over 10 feet in length and the longest on record was 12 feet. Despite being considered highly venomous, very little is actually known about the nature and makeup of the bushmaster's venom because the snakes do remarkably poorly in captivity. Getting samples of venom for study is, therefore, a bit of a hard task.
More dangerous than it looks
The Malaysian krait is a strikingly beautiful snake, but that pattern is there as a warning sign to avoid this species at all costs. Native to Southeast Asia and sometimes called a blue krait, these snakes can be aggressive and their venom is quite hard to deal with. Untreated, bite victims have about a 70% mortality rate and just as concerning is that even when treated, mortality rates only improve to about 50%.
The world's biggest cobra
Forest cobras are the world's largest cobra species, which makes them pretty intimidating even before you know anything else about them. Even though they have a reputation for being aggressive and their venom is highly toxic, there is a small upside to the whole thing. Because forest cobras live in the woods away from people, bites are actually remarkably rare.
The always fatal taipan
Coastal taipans are considered to be about the third most venomous snake in the world as such things are measured, and it's definitely one of the reasons to be careful when you're in Australia. Every bite from a taipan is fatal if it isn't treated quickly, and the venom dose is potent enough to kill 10 adults. Death could occur in as little as 30 minutes but the average time is around 2.5 hours. Rumor has it one person in history managed to survive untreated, but his blood did turn black, so that's weird.
Eastern brown snakes want privacy.
Next to the inland taipan, this may be the most venomous snake in the world. 60% of snakebite deaths in Australia are attributed to this species but there's good news! Or, well, news that can help. Despite their deadliness, they also tend to avoid confrontation when they can and will either hide or flee when confronted. Obviously, there are still issues when humans don't notice the snakes, but if you avoid them, they'll avoid you.
This sea snake is everywhere!
Yellow-bellied sea snakes are some of the most wide-ranging sea snakes in the world and can be found just about anyplace where the water is warm enough. This is the only species of snake that's managed to make its way to Hawaii, so if nothing else they're pretty adventurous. They can be found in New Zealand and California, both of which are usually free of venomous snakes. Weirdly enough, they only drink fresh water which they get from drinking rainwater off the surface of the sea.
One of the Big Four
Russell's viper is considered one of the Big Four snakes, a name given to the four most dangerous snakes in India. These snakes cause more deaths than any other in the country, upward of 25,000 each year, and their bites are also considered to be some of the most painful. They cause intense internal bleeding and necrosis in the affected area, plus it will deliver enough venom to potentially kill upward of 6 people if not treated.
Beautiful but dangerous
Coral snakes are some of the most visually striking snakes in the world and can be found across the US as well as through Central and South America and in Asia as well. Coral snakes have a highly potent venom with a neurotoxin that can cause paralysis before death, but it's worth noting that this is a remarkably rare occurrence. Despite their deadly potential, coral snake bites are not common because the snakes tend to avoid confrontation and, even when they do bite, they don't always envenomate the wound.
More than one reason to avoid a tiger
The western tiger snake accounts for about 17% of all snake bites in Australia. The venom causes a painful reaction that can lead to death, and that's just the start of the reason to steer clear of these snakes. Anyone who harms a tiger snake potentially faces a fine of up to $7,500 and jail time up to a year and a half, giving you extra inventive to not run afoul of one. Worse still, the western tiger is just one of several others that includes eastern, peninsula, King Island, and Chappell Island.
Mambas don't mambo.
Though not the most venomous snake in the world, the black mamba is still one of the most feared. It has a reputation for being aggressive and also remarkably fast, capable of moving at speeds up to 12 miles per hour which, over the uneven terrain in which it lives, is much faster than a human can escape. Compounding the danger is that a black mamba may strike once but bite multiple times in that same strike, each bite injecting more venom.
The king of the cobras
It's good to be king, but not to get bit by one. The king cobra is notable for a number of reasons, not the least of which is that its hiss is of such a low pitch that it can actually sound a bit like a mammalian growl. So it's not bad enough that this is one of the most recognizable and scary snakes in the world but it also growls at you like a bear. Another thing to be wary of is that these snakes will rear up vertically so they look tall, causing victims to often underestimate the safe distance they need to be from one to avoid a bite.
My, what big teeth you have.
No snake in the world can unleash more venom per bite than the Gaboon viper. Maybe it's because they also have the largest fangs of any snakes, growing to a terrifying two inches in length. Those two things together have ensured that the Gaboon also has what is generally considered the world's most painful snake bite. Though not as fatal as many snakes, the bites still bring a host of nightmarish side effects including a loss of bowel and bladder control, convulsions, blisters and necrosis leading to amputation.
Ever seen a saw-scaled viper?
Even though the saw-scaled viper isn't a rattlesnake it's still able to warn off predators or unsuspecting passers-by with a curious ability. It can rub sections of its body together creating a rough, sizzling sound which is a good thing because avoiding this snake is important. The saw-scaled viper is one of the Big Four, meaning it's one of the four most dangerous snakes in India and responsible for thousands of deaths each year.
Common but deadly
The common krait is another of the Big Four snakes from India. Estimates suggest about 10,000 deaths per year are a result of common krait bites. Part of the problem with these snakes is the nature of their bite. Krait bites are not nearly as painful as many snake bites, which can lull a victim into a false sense of security. The bite eventually leads to paralysis, respiratory failure and death. If you don't realize a snake bit you and think it was just an insect, which it can feel like, you may be too late to seek help.
This terciopelo fellow
Also known as the fer-de-lance, the terciopelo is dangerous because it's extremely unpredictable. One moment it may turn to flee, the next it may reel back and attack. Sometimes fearful, sometimes aggressive, they're often described as excitable but that could be to your advantage or very much against it depending on the situation. They're responsible for about half of all the snake bites in Costa Rica and upward of 80% in Venezuela.
Death is its first name.
You probably don't need to be told to avoid a snake called a death adder, but just in case, here we are. They have the fastest strike of all snakes in Australia but despite their fearsome name and demeanor, the species is at risk from one of the most unlikely sources ever — cane toads. The invasive cane toad is doubly deadly for the death adder. Baby adders are at risk of being eaten by the toads and adult adders will eat the toads but then succumb to the toad's poison.
The helpful jararaca
Yes, this South American pit viper can be very deadly but its claim to fame is actually for the entirely opposite reason. The venom of the jararaca is potent and potentially deadly, but it was this specific venom that scientists used in the development of the class of drugs known as ACE inhibitors. You may have heard of those before and probably even know someone who takes them. ACE inhibitors are used to treat hypertension and heart failure.
The worst roommate
The thing about most snakes is that their danger can be ameliorated by the fact they tend to not live near humans, for the most part. Interactions with humans are the exception, not the rule. Unfortunately, no one told that to the Cape cobra. These snakes tend to enjoy living in populated areas in their native Africa. Their thick venom is known to attack the nervous and respiratory system as well as the heart, meaning you never really want this in your home.
Many bands and many bites
A member of the cobra family, the many-banded krait is arguably the most dangerous of all the kraits out there. Even if you receive the anti-venom in time there's still a chance it won't work because their venom is just that potent. Mortality rates for those treated for krait bites are still in the neighborhood of about 50%.
That's no shoe.
The stiletto snake is one of the more unusual venomous snakes in the world. It spends much of its time underground and is very wormlike, but its curved and curiously long fangs pack a dangerous punch. Though not necessarily as deadly as most other species, the venom of a stiletto can cause a severe and gruesome reaction that leads to the affected area swelling and turning black. Amputation of fingers is not uncommon.
How much do you know about dinosaurs? What is an octane rating? And how do you use a proper noun? Lucky for you, HowStuffWorks Play is here to help. Our award-winning website offers reliable, easy-to-understand explanations about how the world works. From fun quizzes that bring joy to your day, to compelling photography and fascinating lists, HowStuffWorks Play offers something for everyone. Sometimes we explain how stuff works, other times, we ask you, but we’re always exploring in the name of fun! Because learning is fun, so stick with us!
Get smarter every day! Subscribe & get 1 quiz every week.
Playing quizzes is free! We send trivia questions and personality tests every week to your inbox. By clicking "Sign Up" you are agreeing to our
and confirming that you are 13 years old or over.