Have you noticed how people often group hamsters and guinea pigs under the same “small pet” umbrella?
Well, that can irk some pet parents who’ve tried raising both mammals. That’s actually understandable once you realize that they have little in common.
What are the key differences? What traits do both pets share?
That’s what our comprehensive hamster vs. guinea pig comparison will cover. We’ll also go over how these differences can get in the way of peaceful cavy-hamster cohabitation.
Hamster vs. Guinea Pig: At a Glance
In a rush? Check out this quick comparison between guinea pigs and hamsters:
| Comparison Point/Pet | Guinea Pigs | Hamsters |
| Family | Caviidae | Cricetidae |
| Origin | South America | Varies by species |
| No. of Varieties | 13 ACBA-recognized breeds | 24 species |
| Sleeping Pattern | Crepuscular | Nocturnal |
| Diet | Herbivores | Omnivores |
| Weight | 25–39 ounces | 3–5 ounces |
| Average Lifespan | 8 years | 18–36 months |
| Sociability | Prefer companionship | Solitary |
| Litter Size | 2–4 pups | 6–8 pups |
| Tail | Absent | Short, stubby |
How Do They Differ?
Let’s dive right into the top 11 differences between hamsters and guinea pigs!
1 – Guinea Pigs are Much Bigger
If you put a cavy next to a hamster, the first distinction you’ll notice right away is the size.
Guinea pigs average around 8–10 inches long and weigh 25–39 ounces. Meanwhile, Syrian hamsters are only 6–8 inches long and weigh 3–5 ounces.
Interestingly, male cavies tend to be larger than their female counterparts, but the opposite is true for the tiny hamsters!
Either way, you’ll want this size difference to reflect in the living space.
According to the Humane Society, a guinea pig needs at least a 7.5-square-foot cage—not that you should be raising a solitary guinea pig, anyway.
On the other hand, 6.25 square feet (900 square inches) will do fine for a hamster, by PetMD’s recommendations.
2 – Guinea Pigs Live Longer
On average, you can expect a cavy to live around 8 years, but it’s not unheard of for those lovable cuddlers to stick around for up to 14 years!
With hamsters, you probably won’t be as lucky; their average lifespan is 18–36 months.
That said, we’d still like to note that not all guinea pigs get to live long.
For one, birthing cavy females live for an average of 3.5 years. That’s because when their joints stiffen up, they’re more likely to suffer from birth-related complications.
3 – Hamsters Are More Likely to Wake You Up
If you hate being woken up at night, hamsters are probably not the right pick for you.
Those borrowers are nocturnal by nature. On the flip side, you’ll hardly hear a squeak during the day.
Guinea pigs are a different story; they’re crepuscular.
This means they’re more active during dusk and dawn. Then, they’ll get short (10–30 minutes) naps during the day.
The catch here is that guinea pigs tend to be rather loud!
So, it’s true that both pets can get rowdy while you’re sleeping. Yet, you’ll have better odds of getting some playtime with a cavy than a hamster.
4 – Guinea Pigs Are More Sociable
Guinea pigs are better raised in groups. They prefer companionship, and aggression shouldn’t be a problem if you introduce the males at a young age.
Once you bond two guinea pigs, it’ll be risky to even attempt to separate them. In fact, the RSPCA recommends keeping at least one companion nearby during veterinary treatments to reduce stress.
By comparison, hamsters are loners.
So, if you don’t want to deal with a group of pets, you can opt for a hamster. The little guy will be perfectly happy with this setup, especially if you go for the Syrian or Chinese varieties.
5 – Hamsters Aren’t Strictly Herbivorous
If you’ve raised guinea pigs before, you’ll know that these fuzzy rascals are strictly herbivorous—absolutely no meat for them!
While hamsters can safely eat seeds and greens, they’re still omnivores. To give them a balanced diet, you’ll have to throw some animal protein (insects, mealworms, etc.) into the mix.
6 – Hamsters Have Larger Litters
Hamster pregnancies last for around 16–22 days, and the mom usually ends up popping out 6–8 little pups at a time.
Guinea pigs have longer gestation periods of a whopping 59–72 days!
Don’t let the extended pregnancy fool you; they usually give birth to 2–4 pups.
7 – Guinea Pigs Are More Accepted Legally
Both cavies and hamsters can be raised as pets, and they’re only getting more popular. Interestingly, Forbes estimates that 30% of Gen Z’s pet owners have either a hamster or a guinea pig.
Yet, hamsters aren’t accepted everywhere. They’re illegal pets in some parts of the world, like Australia.
Although they seem harmless, they can be a risk to biodiversity. After all, they’re omnivorous and can compete with other native animals for resources if they end up establishing a population in the wild.
So, you’ll have a hard time importing a hamster for non-research reasons into Australia!
8 – Guinea Pigs Are Bad Climbers
You’ve probably seen videos of hamsters making their way up intricate tunnels or even climbing up walls and cages.
That’s rarely the case with guinea pigs. Instead, they prefer vertically expanded floor space over walls.
If you set up an 18-inch divider, it’ll be enough of a hurdle to keep the pig locked in place.
9 – Hamsters Store Food in Their Cheeks
Yet another adorable behavior that hamsters are known for is storing food in their cheeks. That’s not something you’ll see a guinea pig doing.
The reason here is simple: guinea pigs don’t have any cheek pouches. Those are the bubbles that expand to allow hamsters to store food so that they don’t have to forage as often.
The interesting thing here is that those pouches don’t only expand to store a few seeds.
A hamster can store up to 20% of his body weight right in those cheeks—a guinea pig could never!
10 – Guinea Pigs Aren’t Built for Exercise Balls
There’s one more thing that hamsters can do but not guinea pigs, and that’s using exercise balls.
Guinea pigs’ backs aren’t flexible enough to enjoy a running ball or wheel safely. Plus, the heat accumulation inside the toy can be too much for a pet to handle.
That’s why even tunnels for guinea pigs have to be made from breathable material.
11 – Guinea Pigs Have No Tails
If you look at their behinds, you’ll notice one final distinction; hamsters have tails, and guinea pigs don’t.
Guaranteed, a hamster’s tail is nothing like the thin, long protrusion you see on a gerbil, but it’s still a tail, nevertheless.
It’s more akin to a fuzzy stub, and that’s more than we can say about the tailless guinea pigs.
How Are They Similar?
Let’s put aside all the differences and look at how hamsters and guinea pigs are similar for a moment.
After all, they’re both small four-footed mammals kept as pets. So, they must have something in common!
1 – They’re Distant Relatives
You’ll find hamsters and guinea pigs listed under the order of Rodentia in the animal kingdom. This order includes around 1,500 species of rodents from different families.
The guinea pigs (cavies) are part of a family called Caviidae, while hamsters fall under the Cricetidae family. Still, they’re distant relatives.
One of the features that prove that guinea pigs belong to the Rodentia order is that they gnaw, just like other rodents.
2 – They Have Ever-Growing Teeth
Speaking of gnawing, hamsters and guinea pigs have incisors that grow continuously throughout their lives.
That’s actually why they keep gnawing on things—they’ve got to manage their teeth length in some way!
3 – They Have Fuzzy Coats
This one might seem like a no-brainer, but both have plushy coats that look similar from a distance.
The catch here is that most hamsters are born hairless and grow into their coats. Meanwhile, guinea pigs show off their luscious coats from day one!
Of course, there are exceptions to the rule, like the hairless skinny pig.
Can Hamsters and Guinea Pigs Live Together?
No, we’d highly recommend against housing hamsters and guinea pigs in the same cage, even if for a short period.
Here’s why:
- Guinea pigs could hurt their backs if they share the hamster’s toys.
- Both pets have different bedding preferences.
- Their sleep patterns aren’t compatible.
- Most hamster species won’t appreciate companionship one bit.
- Guinea pigs could overpower hamsters in a fight, eventually hurting them.
Do Guinea Pigs Eat Hamsters?
It’s hard to say who’d win in a guinea pig vs. hamster fight.
For one, guinea pigs are much larger, so you have to assume they’ll have the upper hand. However, they’re still herbivores, so it’s unlikely that the cavy will eat the hamster up.
Plus, hamsters are fairly aggressive, perhaps even more so than guinea pigs. Add a territorial, solitary nature to the mix, and the little guy might just give the cavy a run for his money!
Can Hamsters and Guinea Pigs Play Together?
It’s not common to see a hamster and a guinea pig getting along well enough to play together.
If you put them in a closed space, odds are, the hamster will be too overwhelmed to consider the cavy as a playmate. You’ll probably even be able to pick up on some signs of fear in the pet’s body language!
You might try to ease the meeting with toys, but that won’t be easy. After all, exercise balls are too dangerous for guinea pigs.
Can Hamsters Eat Guinea Pig Food?
Feeding a hamster guinea pig food once probably won’t kill him. However, just because you can get away with it doesn’t mean it’s not a good idea.
Remember that your hamster is an omnivore rodent that needs a decent protein dose to thrive. That’s not something that guinea pig pellets will be able to provide in the long term.
Instead, you’ll want to give your little rodent a balanced diet of fresh vegetables, seeds, commercial food (gerbil food will do the trick, too), and meat. It’s even possible to give them some chicken or steak as a special treat!
Can Guinea Pigs Eat Hamster Food?
No, you can’t use commercial hamster food for your pet guinea pigs.
They can’t handle seeds (hamsters’ popular snack), either. So, you’ll want to remove seeds from fruits before giving them to your pets.
Ideally, guinea pigs need something rich in fiber and vitamin C. Even hay or alfalfa could be too protein-heavy.
Final Thoughts
Once you take a long look, you’ll see that guinea pigs and hamsters are vastly different creatures.
If you want a small, solitary, low-commitment pet, a hamster might be the way to go. Just be prepared for a nocturnal schedule and a feisty temperament!
On the other hand, guinea pigs can be a suitable pick if you don’t mind raising pets in a group and want some playtime during the day.
I have a bachelor’s degree in Film/Video/Media Studies, as well as an associates degree in Communications. I began producing videos and musical recordings nearly 15 years ago. I am a guitarist and bassist in Southwest MI and have been in a few different bands since 2009, and in 2012 I began building custom guitars and basses in my home workshop as well. When I’m home, I love spending time with my three pets (a dog, cat, and snake) and gardening in my backyard. I also like photographing wild birds, especially birds of prey.