Very strong, but nobody has measured exactly how strong a polar bear is. There is no scientific test of its bite, swipe or lift. What we do know: an adult male weighs 350–600 kg (775–1,300 lb), says Polar Bears International, and one tracked female swam 687 km (426 miles) in nine days.
How strong is a polar bear, really?
You will find exact-looking figures online, such as a bite of “1,235 psi” or a swipe of “59,500 lb-ft/s”. We could not find any study behind them. Nobody has measured a wild polar bear’s bite. A figure in “pound-feet per second” is not even a unit of force.
So the honest way to judge a polar bear’s strength is by what scientists can measure. That means body size, paws and claws, how the skull works, and what the bears actually do. The table sums it up.
| Measure | Figure | What kind of figure | Source |
|---|---|---|---|
| Adult male weight | 350–600 kg (775–1,300 lb) | Typical range | Polar Bears International |
| Adult female weight | 150–290 kg (330–650 lb) | Typical range | Polar Bears International |
| Heaviest male in PBI’s facts | 800 kg (1,700 lb) | One exceptional bear | Polar Bears International |
| Paw width | Up to 30 cm (11.8 in) | Measured | Polar Bears International |
| Claw length | More than 5 cm (2 in) | Measured | Polar Bears International |
| Longest non-stop swim tracked | 687 km (426 miles) in 9 days | Measured with a GPS collar | US Geological Survey study, via National Geographic |
| Blubber eaten in one sitting | More than 45 kg (100 lb) | Estimated | Polar Bears International |
| Bite force | About the same as a brown bear’s | Computer model of the skull | Slater et al. 2010 |
| Lift or swipe force | Never measured | Unknown | No study found |
Why are polar bears so strong?
Size comes first. A big male can weigh up to 800 kg, about as much as ten men, says WWF-UK. More body means more muscle to push, pull and pin down a seal.
Their way of life needs that power. A polar bear lives mainly on seals, which it grabs at breathing holes or catches resting on the ice. WWF-UK says fewer than 2% of polar bear hunts succeed. So a bear must strike hard and fast every time it gets a chance. Our page on what polar bears eat explains the seal diet.
Fat is the fuel. When hunting is good, a bear can eat more than 45 kg (100 lb) of blubber in one sitting, says Polar Bears International. That stored energy powers long walks, long swims and the lean months.
How strong are a polar bear’s paws and claws?
Nobody has measured their force, but their size is clear. A polar bear’s paws can be 30 cm (almost 12 in) across, about the size of a dinner plate. Each claw is more than 5 cm (2 in) long, according to Polar Bears International. Small bumps on the foot pads, called papillae, help the bear grip the ice.
Big paws spread a heavy bear’s weight on thin ice and work like paddles in water. The claws hook seals and hold on to slippery ice. Our guide to polar bear adaptations explains more.
How strong is a polar bear’s bite?
Probably about as strong as a brown bear’s, but its skull is weaker. In 2010, scientists built computer models of polar bear and brown bear skulls and tested pretend bites. The polar bear’s bite came out about the same, even slightly stronger. But its skull bent more and carried much higher stress, up to 408% higher in bites with the back teeth, report Slater and colleagues.
The reason is diet. Brown bears grind tough roots and plants, which takes a sturdy skull and big chewing teeth. Polar bears eat soft blubber and meat, so their skull became lower and flatter. It is a good tool for seals and a poor one for crunching hard food.
How far can a polar bear swim?
Farther than most people would guess. A US Geological Survey study tracked female polar bears with GPS collars in the Beaufort Sea off Alaska. One swam 687 km (426 miles) over nine days without stopping, reports National Geographic. She lost 22% of her body weight, and her cub did not survive.
That swim shows huge stamina, but it is also a warning sign. Long swims like this happen when the sea ice melts far from shore. Our page on how fast a polar bear can swim covers speed in the water.
On land, polar bears are built for walking, not racing. They can run for a short distance but soon overheat, says Polar Bears International. See how fast a polar bear can run for the numbers.
Is a polar bear stronger than a grizzly bear?
Nobody has tested them side by side, so we can only compare size. Adult male polar bears usually weigh 350–600 kg (775–1,300 lb). The US National Park Service gives brown and grizzly bears 91–454 kg (200–1,000 lb), depending on sex, place and season. So most polar bears are heavier, and a heavier animal usually carries more muscle.
Heavier does not always mean stronger in a fight. Grizzlies have a sturdier skull and a big shoulder hump of digging muscle. For their side of the story, read how strong is a grizzly bear and polar bear vs grizzly bear size.
How strong is a polar bear compared with a human?
There is no fair test, but the size gap says a lot. A big male can weigh as much as about ten men (WWF-UK). Standing on its hind legs, it is over 3 m (10 ft) tall, says Polar Bears International. No person could hold one back.
That is why people in polar bear country follow safety rules. Parks Canada advises staying in a group, backing away slowly without running, and carrying deterrents such as bear spray. If a polar bear stalks or charges, it says to stand your ground and fight back. Adult polar bears have few enemies of their own; see what eats polar bears.
Frequently asked questions
How much can a polar bear lift?
Nobody knows, because no one has ever measured it. Figures you see online are guesses. What we do know is that an adult male usually weighs 350 to 600 kg (775 to 1,300 lb) and can haul seals out of the water and across the ice. Treat any exact lifting number with suspicion.
Where does the 1,235 psi polar bear bite figure come from?
We could not trace it to any study. No one has measured a wild polar bear biting a sensor. The best scientific work, a 2010 computer model of bear skulls, found that a polar bear's bite is about as strong as a brown bear's, but its skull is weaker and bends more under load.
Is the polar bear the strongest bear?
It may be, but nobody has tested it. The polar bear is one of the two biggest bears, level with the Kodiak brown bear, and bigger animals usually have more muscle. But strength has never been measured in any wild bear, so no one can say for sure which bear is strongest.
Are polar bears dangerous to people?
They can be, so people in polar bear country take care. Parks Canada advises staying in a group, never running, backing away slowly and carrying deterrents such as bear spray. If a polar bear stalks or charges, Parks Canada says to stand your ground and fight back, aiming at the face and nose.
Sources
- Polar Bears International. 10 surprising facts about polar bears.
- Polar Bears International. Adaptations and characteristics.
- Polar Bears International. Polar bear behavior.
- WWF-UK. Top 10 facts about polar bears.
- PLOS ONE (2010). Biomechanical consequences of rapid evolution in the polar bear lineage (Slater et al., PLoS ONE, doi:10.1371/journal.pone.0013870).
- National Geographic (2011). Longest polar bear swim recorded: 426 miles straight (on the USGS study by Pagano et al.).
- US National Park Service. Brown bears.
- Parks Canada (Wapusk National Park). Handling an encounter: polar bear safety.
Sources checked 15 September 2026.
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