You see squirrels everywhere, right? Ever catch yourself wondering just how big they actually get? Most common tree squirrels tip the scales somewhere between 7 ounces and 2 pounds, though species and season really shake things up.
This post dives into typical weights, compares the main types you might spot, and takes a stab at explaining why a squirrel’s size changes with food or weather.
You’ll pick up some quick tricks to figure out which squirrel you’re looking at and what kind of weight you can expect.
How Much Does a Squirrel Weigh?
Squirrel weights? They’re all over the place, honestly. It depends on the species, age, and even the time of year.
You’ll find tiny tree squirrels that fit in your palm, and then there are the beefier ground or flying squirrels that can weigh a pound or more.
Squirrel Weight by Species
Different squirrel species come in all sorts of sizes. Eastern gray squirrels usually weigh 14–21 ounces (400–600 g).
Fox squirrels? Those are bigger, often hitting 1.5–2.5 pounds (680–1,130 g). Red squirrels stay smaller at about 7–14 ounces (200–400 g).
Flying squirrels, since they need to glide, weigh less—commonly 1.5–7 ounces (42–200 g).
The African pygmy squirrel is just tiny—about 10–14 grams. It’s honestly wild how small they are.
Diet, habitat, and season really change a squirrel’s weight. Many tree squirrels pack on fat before winter and then slim down by spring.
Average Weight of a Squirrel
When someone asks about the average squirrel weight, they’re usually thinking of the common tree species near their home.
For those, you’re looking at around 14–21 ounces (400–600 g).
If you count every squirrel worldwide—ground, tree, flying, and pygmy—the average drops, since there are so many little species.
It’s better to use species-specific numbers. For example, Eastern gray squirrels are 400–600 g, while red squirrels are more like 200–400 g.
Weight of Adult Squirrels
Adult weight? That depends on sex, health, and season.
Healthy adult Eastern gray squirrels often weigh 400–700 g.
Pregnant or well-fed adults can weigh more. Squirrels getting ready for winter might bulk up by 10–30% compared to their summer selves.
Younger adults still growing will weigh less than the older ones. If you spot an adult that looks skinny, it might be sick or just struggling to find enough food.
Notable Extremes: Smallest and Largest Squirrels
The African pygmy squirrel holds the record for smallest at about 10–14 grams. You could hold one in your hand and barely notice the weight.
Some ground squirrels and marmots get pretty big; certain tree squirrels like the fox squirrel can weigh over 1 kg, though that’s rare.
Records can vary a lot by species and location. For everyday squirrel watching, it’s best to stick with the usual ranges.
You can find more on typical backyard squirrel weights in this guide on how much a squirrel weighs.
Different Types of Squirrels and Their Weights
Here’s a quick look at typical weight ranges and what sets the common squirrel groups apart.
Sizes really jump around by species, where they live, and the time of year. Check out these ranges.
Tree Squirrels
Tree squirrels, like the Eastern gray and fox squirrel, make their homes in forests and cities.
Eastern grays usually weigh in at 400–600 grams (14–21 oz).
Fox squirrels can get bigger, often reaching 500–1,000 grams (18–35 oz).
Urban squirrels sometimes get heavier because people feed them. In the fall, many tree squirrels bulk up for the cold months ahead.
Some quick facts:
- Diet: mostly nuts, seeds, fruit, and sometimes insects.
- Length: bigger species can stretch to 45–50 cm, tail included.
- Weight can affect agility. Heavier squirrels still climb well, but they might not be as quick on the skinny branches.
If you’re in North America and spot a squirrel at the park, it’s probably an Eastern gray. Elsewhere, check local species lists for better numbers.
Ground Squirrels
Ground squirrels include the California ground squirrel and marmots.
Smaller ones often weigh 200–500 grams (7–18 oz).
Marmots and alpine squirrels can hit a few kilograms once they’re fully grown.
These guys spend more time on the ground and store fat for hibernation.
A few things to know:
- Hibernators bulk up in the fall, so their weight can swing a lot.
- Diet: seeds, roots, grasses, and the occasional insect. What they eat shows up in their body mass.
- Bigger ground squirrels can scare off some predators, but they need more food to keep going.
If you spot a small ground squirrel, expect 250–400 grams. Marmots? They’re much heavier, definitely a few kilos.
Flying Squirrels
Flying squirrels don’t actually fly—they glide. They need to stay light to make those glides work. If you look at North American flying squirrels like the Northern flying squirrel, you’ll usually find they weigh somewhere between 100 and 230 grams (about 3.5 to 8 ounces).
Some of the tropical species get a bit bigger, but honestly, most flying squirrels weigh less than 500 grams.
Why do they need to be so light? Well, that stretchy membrane along their sides—the patagium—works best if their bodies aren’t too heavy. It gives them way more control in the air.
Their diet plays a part, too. They munch on nuts, fungi, fruits, and insects, which keeps their size in check.
And since flying squirrels are mostly nocturnal, spotting one (or even guessing its weight) isn’t always easy.
If you’re wondering how they stack up against other squirrels, flying squirrels are usually the lightest. Tree and ground squirrels? They tend to be much heavier.
