Guinea Pigs 101: Size, Lifespan, Breeds & Habits

Guinea pigs are small, gentle, social pets with surprisingly big personalities. They squeak when they hear the fridge open, popcorn when they are happy, and can quickly become a much-loved part of the family. But despite their small size, guinea pigs need more care and attention than many new owners expect.

If you are thinking about getting a guinea pig, you may have questions like: Are guinea pigs actually pigs? How big do they get? Can they live alone? Are they friendly? And how are they different from hamsters?

This guide answers these common questions and helps you understand what guinea pigs are like, how they behave, and what they need from their owners. Let's start with the basics.

Guinea pigs (scientific name Cavia porcellus) are small rodents. They are not pigs nor rats. They are also known as cavies. The name is a riddle. They are not from Guinea, nor are they pig relatives. It is unclear how the name started.

The origin of the Guinea pig is South America. Guinea pigs are now domesticated animals! They also have a place in scientific research in the old days as they are easy to maintain and are very small. That’s where the phrase, “I was the guinea pig” is from.

Guinea pigs size can vary, but adult guinea pigs typically weigh between 700g and 1.5kg and are approximately 20–35cm long. They are small enough to fit in your hand, but larger than a hamster. Guinea pigs age is another important factor to consider before bringing one home. Guinea pigs' lifespan is 5–7 years with proper care, although some may live a little longer. It’s a long-term commitment, so consider this before you purchase. The young of guinea pigs are called pups. They are born furred and have open eyes, and can move about within hours. If the guinea pig is pregnant, consult a veterinarian for treatment of small animals.

There are a lot of guinea pigs breeds and kinds. The most frequent ones are:

Long hair looks great, but must be brushed regularly. A short haired guinea pig is easier for a first time owner.

Looking for supplies for your guinea pig? Explore our Guinea Pig Products page for food, accessories, housing essentials, and other products for guinea pig care.

Are guinea pigs and hamsters the same? No. Here is the difference between guinea pigs and hamsters:

So, guinea pigs or hamsters? Guinea pigs are a more suitable option if you prefer a pet that is awake during the day, enjoys socializing, and lives longer. They need more room and more daily care, though. If you are considering a hamster instead, read our Hamster Guide to learn more about their behaviour, care, diet, and housing needs. DO NOT keep guinea pigs and hamsters together.

Most are gentle. Are not aggressive in nature. They act calmly and slowly, they become accustomed to humans. Pick the whole body up when lifting them.

Rarely. A bite typically indicates fear or pain or a rough handling. Allow them a couple of days to get used to their surroundings before you do much with them.

Guinea pigs are social animals. Even a loving owner will not be able to keep a guinea pig from getting lonely and bored. So don't forget to maintain at least two. Most of the time two Guinea Pigs of the same sex will team up well. A mixed pair can make babies so consult a vet or experienced keeper before you mate a male and a female.
Not every pair gets along at once. Some chasing is normal in the first days. Serious fighting is not. If that happens, separate them.

No, they do not come out at night. Guinea pigs are most active at dawn and dusk. They are also awake for a lot of the day, and nap around the clock, with eyes open.

Not well. They use their sense of smell, their ears and their whiskers.

Some will, in one corner. They don't work as effectively as cats, though. Plan to clean the cage often.

They eat all day, and their diet is high in fibre. They are constantly working on their gut and make lots of drops. This is normal. They also consume some of their own soft droppings. It's normal for them as well.

The important thing is a change. See vet immediately if droppings become smaller and/or less firm or cease.

They run, they hide in tunnels, they chew, they search for food, and of course, they play with their friends. They can jump up and jump down with joy sometimes. Owners refer to this as “popcorning”.

They talk a lot:

No. They are plant eaters. But guinea pigs can fight, so watch new pairs closely and separate them if the fighting is serious.

Now that you know what guinea pigs are like and how they behave, it’s time to learn how to care for them properly.

In this next article, we cover what they should eat every day, how big their cage really needs to be, the cost of keeping them in India, and the important signs that mean it’s time to visit a vet.

→ Read Guinea Pig Care Guide – Food, Housing, Cost & Health