Pick a hamster if you want one small, quiet pet that lives alone and is happy to be watched more than held. Pick rats if you want a pet that climbs onto your shoulder and actually seeks you out, and if you have room for two of them, because rats should never live alone. Both live only a few years, both are awake when you’re winding down, and both need a much bigger cage than the pet store’s starter kit.
Matt here. I’m not a vet, so a sick or hurt pet of either kind goes to a vet who sees small pets. For the choice itself, though, the differences are pretty clear once you line them up, and it’s way easier to sort out before anybody comes home in a cardboard box.
One Hamster, or Two Rats at Minimum
This is the biggest difference, and it changes everything else on the list.
Rats are social animals that should never be kept alone. They play together, sleep in a pile and groom each other, and the usual advice is a bonded pair or trio of the same sex. So “getting a rat” really means getting two rats, two sets of vet bills and a cage built for a group.
A Syrian hamster is the opposite. Syrians, and Chinese hamsters too, are better kept on their own and can turn on a cage-mate, sometimes badly. Dwarf species like the Roborovski or the winter white can share a home with the right setup, but plenty of owners still end up splitting pairs that stop getting along. If you want exactly one animal, the hamster is your furry friend.
How Long Each One Lives
Neither one is a long-haul pet, and that’s worth saying out loud to a kid before you buy. Hamsters usually live up to about 2 years, sometimes a bit longer. Pet rats live around 2 to 3 years, and females tend to outlast males.
Here’s a fun way to picture how fast a rat’s life moves: one month of a rat’s life is roughly 2.5 years of ours. By age 3, a rat is something like 90 in human years. So old age shows up fast. When either pet slows down, stops eating or breathes hard, that’s a same-day call to a small-pet vet.
There’s more on why most hamsters top out where they do in our post on whether hamsters really live for 2 years.
Who’s Awake When You Are
Both of these are night animals, so don’t expect much from either one at 2 in the afternoon.
Hamsters wake up around dusk and get busy at night. Wild ones can run up to five miles a day, which is why a good wheel matters so much, and why a squeaky one in a bedroom gets old fast. A hamster shouldn’t be woken up for handling either. Poke one out of a deep sleep and you’re far more likely to get nipped.
Rats are mostly awake at night, at dusk and at dawn, and sleep through the day. The good part is that they’ll often shuffle out to say hi in the morning and evening, which lines up nicely with a school or work schedule. They also hear really well, so the cage shouldn’t sit next to a TV, a speaker or the washing machine.
For a light sleeper, I’d keep either cage out of the bedroom. A hamster digging and running at 3 a.m. is louder than you’d think, and a group of rats wrestling over a hammock isn’t quiet either. A living room or a spare room works better for everyone, and it puts the cage where you’ll actually sit with them in the evening.
Which One Likes Being Held
This is where rats honestly win. Rats are easier to handle than smaller rodents like hamsters, and most of them enjoy time with their people. A tame rat will often come to the cage door to greet you and happily ride around on a shoulder. They can still bite when they’re scared, like any small animal, so kids need an adult nearby.
A hamster can absolutely get tame. It just takes longer, and most of them stay a bit more “let me sit in your hand for a minute, then put me down.” They’re small, they’re quick, and a fall from a standing kid’s hands can hurt one badly. Hold your little buddy low over a couch or the floor until it trusts you.
If your hamster has already nipped someone, our guide to why hamsters bite covers the usual reasons and how to fix them.
How Big the Cage Really Needs to Be
Here’s where people get surprised, with both pets.
A Syrian hamster needs about 900 square inches of floor, roughly 40 by 22.5 inches, and a cage 24 inches tall so it can hold at least 10 inches of bedding to burrow in. Dwarf hamsters need about 700 square inches. Most of the tube-and-pod cages at the pet store are too small, and the wheels that come with them are too small for a Syrian’s back. A hamster lives on the floor, so floor space matters more than levels.
Rats live up and down. Give them at least 2 cubic feet of cage per rat, so a pair needs 4 or more, with shelves and ramps to climb (and a hammock or two, which most rats love). If you add a wheel, it should be solid and at least 11 inches across. And rats need time out of the cage every day to explore, with you watching, so you’ll want a rat-safe room too.
Short on space? Our guide to a hamster cage for a small apartment shows how to fit the floor space into a tight room.
What Each One Eats, and What Stays Off the Menu
Feeding is pretty simple for both, and both start from a food made for that animal.
Wild hamsters eat seeds, grains, insect larvae and bigger bugs like crickets. At home, the base is a pellet or a seed mix made for hamsters, plus small bits of greens, washed root veggies and fruit like apple. Change foods slowly, toss anything stale, and keep grapes and rhubarb out of the cage. You’ll also see your hamster stuff its cheeks and run off to the nest. That’s normal. It eats in private or stashes food for later, so the “missing” food is usually sitting in the bedroom.
Rats eat almost anything, which is exactly why you have to watch them. The base is a rat pellet, with small amounts of fruit and veggies on top, plus a little cooked egg, grain or seed now and then. The list to skip is longer: onion, citrus fruit, walnuts, rhubarb, grapes and raisins, plus chocolate. Rich treats are best saved as rewards, which works nicely because rats learn fast when food is on the line.
Water is where the two setups really differ. A group of rats needs several bottles so they can all drink at the same time. A hamster needs one bottle that’s easy to drink from, because hamsters can’t suck very hard on a stiff spout. Check the bottle every day for both, since a jammed spout is easy to miss.
And make dinner a game. Scatter food around the cage, mix some into fresh bedding when you clean, or hide a treat in a cardboard tube. Rats will happily chew their way in, and hamsters love to sit up and work on a piece of food with their front paws. If either one stops eating, though, skip the guessing and call a small-pet vet that day.
Cleaning and Smell: The Weekly Work
A hamster is the lighter load. Spot-clean the dirty bedding and old food every few days, and do a full clean once or twice a month. Hamsters usually pick one corner as a bathroom, which helps a lot.
Rats want a full clean once a week, plus the daily out-of-cage time, plus two or three animals’ worth of food and bedding. They’re clean animals that keep their toilet spot away from where they sleep, but a group of rats in a closed room does smell more than one hamster. Skip dusty sawdust and aspen bedding for rats, which can bother their breathing.
Either way, clean when they’re awake, in the evening, not in the middle of the day. Tearing up a sleeping animal’s nest is stressful for it.
So Which One Fits Your Home?
The better pet for your home depends on how much you want to hold it and how much room you have.
If you want a pet to watch, with a short bit of hand time in the evening, and you have space for one big floor-level cage, a Syrian hamster is a great fit. If you want a pet that hangs out with you, rides around on your shoulder, and you can give a pair of rats a tall cage plus supervised play time every day, rats are way better at that job.
Whichever way you go, I’d plan the cage before the pet. The starter kits sold beside the animals are where most first-time owners go wrong, with both rats and hamsters. Buy the big cage, set it up, and then go pick out your new roommate (or roommates). It’s way less stressful for everybody than an upgrade a month later.
One more thing. An adult should own the care of either pet, even if it’s “the kid’s hamster.” Kids can help with feeding and cleaning (and they’ll happily take the play part), but a grown-up should check the water bottle, notice a pet that isn’t eating, and make the vet call. Weighing up other small pets too? Our hamster vs gerbil comparison is the next one to read.