So, you’re picturing a massive white bear and a burly brown one—who’s actually bigger? Polar bears usually outsize grizzly bears, especially when you look at adult males. But some brown bear subspecies, like Kodiaks, can come close or even match polar bears in size. That’s not just trivia—it matters for how these animals hunt, survive, and even how strong they are.
You’ll find real size numbers here, plus a look at how body shape and fat change the whole picture. I’ll also get into where Kodiak and other brown bears fit in. Honestly, it’s not always as simple as “polar bears are bigger,” and habitat and diet play a huge role.
Comparing the Size of Polar Bears and Grizzly Bears
Polar bears and grizzly bears mostly differ in weight, body length, and overall build. Adult male polar bears tend to be heavier, while grizzlies pack more muscle and have stronger forelimbs.
Their size changes depending on region, season, and how healthy they are.
Average and Maximum Weight Comparison
Adult male polar bears (Ursus maritimus) usually weigh somewhere between 700 and 1,500 pounds. Females are smaller, often in the 300–700 pound range.
That thick blubber layer on polar bears isn’t just for show—it adds a lot of mass and keeps them warm in freezing Arctic waters.
Male grizzly bears (a type of Ursus arctos) often weigh 400 to 800 pounds, and females typically hit 200–400 pounds. Some coastal brown bears and Kodiaks, who are close cousins, can get even heavier. That’s where the size gap starts to shrink.
On average, polar bears come out heavier. But at the extreme end, the biggest grizzlies and coastal brown bears can rival the largest polar bears. Food supply and the time of year (before or after a big hunt) can make their weight swing a lot.
Height and Body Length Differences
On all fours, polar bears can stand 4.5 to 5.5 feet at the shoulder. If they stand up, some males reach 10 feet tall.
Their body length usually runs 7.5 to 10 feet from nose to tail.
Grizzly bears, on all fours, stand around 3.5 to 4.5 feet at the shoulder. Upright, adult males often reach about 8 feet, maybe a little more.
Their bodies stretch 6 to 8 feet long.
Polar bears have longer necks and a more stretched-out skull, perfect for hunting seals on the ice. Grizzlies, meanwhile, have a compact, muscular shape with a big shoulder hump.
So, even if the numbers are close, polar bears look longer and leaner, while grizzlies just look stockier.
Biggest Polar Bear and Grizzly Bear Records
The biggest polar bear ever confirmed weighed around 2,209 pounds, way back in the early 1900s. That’s not something you’ll see these days—most big modern males are under 1,700 pounds.
For grizzlies and brown bears, some records mention individuals close to 1,500–1,700 pounds, mostly Kodiaks and coastal bears with lots of food. Weights above 1,700 pounds are extremely rare and usually come from old or sketchy reports.
These record-breakers are outliers. Most polar bears and grizzlies you’ll ever come across are much lighter. Local habitat and what they eat make the biggest difference in how large a bear can get. Want more details? Check out this polar bear vs grizzly bear size comparison.
Other Giant Bears: Where Kodiak Bears Fit In
Kodiak bears are a brown bear subspecies (Ursus arctos) that can seriously compete with the largest polar bears. Let’s see how Kodiaks stack up in height and weight, and meet a couple of famous giants.
Kodiak Bear vs Polar Bear and Grizzly Bear Size
Kodiak bears (Ursus arctos middendorffi) are some of the heaviest brown bears out there. Wild adult males commonly weigh 800–1,400 pounds, and when they stand up, they can hit 8–10 feet tall.
Females are smaller, usually topping out around 700 pounds.
Polar bears, at their biggest, can go over 1,500 pounds. So the very largest polar bears out-weigh most Kodiaks, but plenty of big Kodiak males overlap with the lower end of big male polar bears.
Grizzly bears (another brown bear form) are generally smaller—males usually hit 300–800 pounds—so Kodiaks are often obviously bigger than your average grizzly.
Diet and habitat are the main reasons for these differences. Kodiaks eat salmon, berries, and coastal foods that help them bulk up. Polar bears feast on high-fat marine prey, making some of them even heavier.
You could say Kodiaks and polar bears are neck-and-neck at the top, but Kodiaks usually outsize most grizzlies.
Notable Grizzly Bear and Kodiak Bear Individuals
People sometimes talk about record-breaking bears that really push the limits. Take Clyde, for example—a famous captive Kodiak. He once tipped the scales at over 2,100 pounds. That’s wild, right? It just shows how massive Ursus arctos middendorffi can get when humans care for them.
Wild Kodiaks don’t usually reach that kind of size. Still, some big males on the islands have weighed more than 1,400 pounds.
Grizzlies, on the other hand, are generally smaller. Most wild male grizzlies in North America don’t get much past 1,000 pounds.
Seeing these named bears—Kodiaks, polar bears, or grizzlies—kind of puts things in perspective. Some individuals break records, but most fall closer to the average.
Want more specifics about their sizes? You can check out the size comparison at A-Z Animals for details on polar and Kodiak bear figures.
