You’ve heard the stories — a snake so venomous it can drop an elephant with a single bite, a creature that deserves its royal title. But the king cobra is far more interesting than the myths suggest, and here’s what the science really says about its venom, behavior, and your odds of surviving an encounter.
Average length: 3.18–4 m (10.4–13.1 ft) · Maximum recorded length: 5.85 m (19.2 ft) · Venom yield (dry weight): Up to 420 mg per bite · Geographic range: South and Southeast Asia · Conservation status: Vulnerable (IUCN Red List)
Quick snapshot
- King cobra venom can kill an adult elephant with a single bite (Smithsonian’s National Zoo).
- The species is the longest venomous snake in the world (Wikipedia). (Smithsonian’s National Zoo)
- King cobras eat other snakes, including other cobras (Smithsonian’s National Zoo). (Smithsonian’s National Zoo)
- They are generally not aggressive unless provoked (Nature Safari India).
- Exact population numbers across the range are unknown (PMC review).
- The taxonomic status of the king cobra as a species complex is still debated (PMC review). (PMC review)
- Precise LD50 values vary between studies (PMC review). (PMC review)
- Death can occur within 30 minutes to a few hours without treatment (PMC review).
- Immediate medical care and species-specific antivenom are critical for survival (PMC review).
The king cobra is a snake of superlatives — but also of nuances. Here are the essential facts that define Ophiophagus hannah.
| Attribute | Value | Source |
|---|---|---|
| Scientific name | Ophiophagus hannah | PMC review |
| Average length | 3.18–4 m (10.4–13.1 ft) | Wikipedia |
| Maximum length | 5.85 m (19.2 ft) | Wikipedia |
| Weight | Up to 12 kg (26 lb) | Wikipedia |
| Venom yield (dry) | Up to 420 mg per bite | Facts and Details |
| Diet | Snakes (ophiophage) | Smithsonian’s National Zoo |
| Geographic range | South and Southeast Asia | Smithsonian’s National Zoo |
| Conservation status | Vulnerable (IUCN) | IUCN Red List |
How venomous is a king cobra?
How does king cobra venom compare to other snakes?
- King cobra venom is primarily a neurotoxin that attacks the central nervous system (Smithsonian’s National Zoo).
- Although highly potent, it is not the most venomous snake — that title belongs to the inland taipan (Wikipedia).
- The king cobra’s danger comes from the large volume it can inject: reportedly up to 420 mg of dry venom per bite (Facts and Details).
What is the LD50 of king cobra venom?
- LD50 values vary across studies, but one common reference for mouse intravenous injection is around 1.2 mg/kg (Wikipedia).
- By comparison, the inland taipan’s LD50 is roughly 0.025 mg/kg, making it over 40 times more potent by volume (Wikipedia).
How much venom does a king cobra inject?
- A single strike can deliver enough venom to cause fatal envenomation, and clinical reports describe antivenom doses ranging from 20 to 115 vials (PMC review).
- The Thai species-specific antivenom (OhMAV) shows variable neutralization: it works best against Thai venom, but requires much higher doses for Malaysian, Indonesian, and Chinese venom samples (PMC review).
- The implication: venom composition varies regionally, so antivenom effectiveness depends on where the bite occurred.
The king cobra’s venom isn’t the most toxic on a milligram-for-milligram basis, but its sheer volume — enough to kill an adult elephant — makes it one of the most dangerous snakes in the world. Regional venom variation adds a complication: a victim bitten in Malaysia may need three times more antivenom than one bitten in Thailand.
The pattern: a snake that delivers a massive payload of neurotoxin, with treatment success hinge on both time and geography.
The king cobra’s lethal reputation rests on venom volume and regional variation, not raw toxicity per milligram.
Has a king cobra killed a human?
How many people die from king cobra bites each year?
- King cobra bites are rare, and annual fatalities are estimated in the dozens, not hundreds, largely because the snake avoids humans (PMC review).
- When bites do occur, they are often fatal without prompt medical treatment (Smithsonian’s National Zoo).
What happens after a king cobra bite?
- The neurotoxin quickly attacks the nervous system, causing blurred vision, drowsiness, and eventually respiratory paralysis (PMC review).
- Death can occur within 30 minutes to a few hours if antivenom is not administered (PMC review).
Antivenom doses reported: 20–115 vials · OhMAV ED50 (Thai venom): 39.47 µL · OhMAV ED50 (Chinese venom): 170.16 µL
The pattern is clear: geography matters. A victim bitten in Thailand has a better chance with local antivenom than someone bitten in Malaysia or Indonesia. This regional variation is a critical factor that clinicians must account for.
Fatality from king cobra bite is rare but rapid without antivenom, and regional venom differences complicate treatment.
Why is king cobra not aggressive?
How does king cobra behavior differ from other cobras?
- King cobras are generally shy and will avoid humans whenever possible (Nature Safari India).
- They are considered intelligent and can learn patterns of human activity, often retreating before people even see them (Smithsonian’s National Zoo).
- When threatened, they raise a third of their body, spread a dramatic hood, and emit a low growling hiss — a warning that gives you time to back away (Nature Safari India).
What triggers a king cobra to strike?
- They become aggressive only when cornered, threatened, or guarding a nest (Nature Safari India).
- Females are particularly defensive during the breeding season, when they build a leaf nest and guard the eggs fiercely — a rare behavior among snakes (Smithsonian’s National Zoo).
Despite being the longest venomous snake in the world, the king cobra is one of the most reluctant to bite humans. Its reputation as an aggressive killer is largely a myth — most encounters end with the snake retreating rather than attacking.
What this means: the snake’s shy nature, combined with clear warning signals, reduces risk for people who keep their distance.
King cobra aggression is a myth; the snake avoids conflict and gives ample warning before any potential strike.
Which animal kills king cobra?
Do mongooses prey on king cobras?
- Mongooses are known predators of venomous snakes, including king cobras, though the size and strength of a king cobra make it a challenging meal (National Geographic).
- Mongooses rely on speed and agility — and some have evolved partial resistance to neurotoxins (Wikipedia).
What other predators hunt king cobras?
- Large birds of prey, such as serpent eagles, regularly take king cobras (National Geographic).
- Humans are the primary threat through habitat destruction, road mortality, and deliberate killing out of fear (IUCN Red List).
The trade-off: king cobras are apex predators within their snake-eating niche, but they face growing pressure from human encroachment. Their vulnerable conservation status reflects this precarious balance.
Despite few natural predators, human activity poses the greatest threat to king cobra survival.
Can you survive if you get bit by a king cobra?
What is the first aid for a king cobra bite?
- Survival depends on staying calm, immobilizing the bitten limb, and getting to a hospital immediately (PMC review).
- Do not cut the wound, suck out venom, or apply a tourniquet — these common mistakes increase tissue damage (World Health Organization).
How important is antivenom treatment?
- Species-specific antivenom is the only effective treatment, and it must be given quickly (PMC review).
- In Thailand, the antivenom OhMAV is available, but its effectiveness varies by region — patients from outside Thailand may need much higher doses (PMC review).
The biggest danger is not the snake’s aggression — it’s the distance to a hospital with antivenom. In rural parts of South and Southeast Asia, a victim may have hours of travel, and the clock starts ticking the moment the fangs sink in.
Survival factor #1: Time to antivenom · Survival factor #2: Geographic match of antivenom · Survival factor #3: Calm immobilization
For anyone living or traveling in king cobra territory, the takeaway is clear: know where the nearest hospital with antivenom is, and never try to handle or provoke the snake. Your best defense is respect and distance.
Survival depends on immediate medical care and geographic match of antivenom; distance to care is the critical variable.
Clarity check: confirmed vs. what remains unclear
Confirmed facts
- King cobra venom can kill an adult elephant with a single bite (Smithsonian’s National Zoo).
- King cobra is the longest venomous snake in the world (Wikipedia).
- King cobras eat other snakes, including other cobras (Smithsonian’s National Zoo).
- They are generally not aggressive unless provoked (Nature Safari India).
- Thai antivenom shows variable neutralization across geographic venoms (PMC review).
What’s unclear
- Exact population numbers across the range are unknown (PMC review).
- Taxonomic status as a species complex is still debated (PMC review).
- Precise LD50 values vary between studies (PMC review).
- Juvenile venom potency relative to adults: some sources say equally potent, others suggest variation (Facts and Details).
What the experts say
King cobras are impressively venomous, but they are also shy and reclusive. They will almost always choose to flee rather than fight.
— Smithsonian’s National Zoo
King cobras are known to eat other snakes, including other cobras. This is why they are called ‘king’ cobras.
— Smithsonian’s National Zoo
The average length of a king cobra is 10 to 13 feet (3 to 4 meters), and the longest recorded specimen was 19.2 feet (5.85 meters).
— Wikipedia
King cobras can grow up to 18 feet (5.5 meters) and live in forests and swamps in parts of Asia.
For anyone who shares the landscape with this snake, the message from experts is unanimous: respect the king cobra, but don’t fear it. Your safety depends on understanding its behavior, not exaggerating its threat.
Frequently asked questions
What is the scientific name of the king cobra?
Ophiophagus hannah — a name that means “snake-eater” (Wikipedia).
How fast can a king cobra move?
King cobras can slither at speeds up to 7–8 mph (11–13 km/h) in short bursts, though they rarely chase humans (National Geographic).
Are king cobras endangered?
The king cobra is listed as Vulnerable on the IUCN Red List due to habitat loss and persecution (IUCN Red List).
Do king cobras have any natural predators besides humans?
Yes — mongooses, large birds of prey like serpent eagles, and occasionally other large snakes (National Geographic).
How many eggs does a female king cobra lay?
A female typically lays 20–40 eggs in a leaf nest, which she guards until they hatch (Smithsonian’s National Zoo).
What should you do if you encounter a king cobra in the wild?
Stop moving, back away slowly, and give the snake plenty of space. Do not make sudden movements or try to provoke it (Nature Safari India).
Can king cobras spit venom like some other cobras?
No — king cobras do not spit venom. They inject it through hollow fangs (Smithsonian’s National Zoo).
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