Guinea pigs are very popular rodents as house pets but before adopting a guinea pig, you may want to know about their size, growth, or weight. As any other animal, guinea pigs can also vary in size. They can grow much bigger than other rodents such as mice, hamster and rats.
Cavies do not have tails which makes it easy to measure their length. Guinea pigs are usually 8-12 inches(20-30cm) long. Their length depends on many factors such as maturity, growth, breed or male/female.
Let’s look more in detail about their size.
Basic Size Chart
|Birth||3-4 inches (8-10 cm)|
|8 weeks||6-8 inches (15-20 cm)|
|16 weeks||8-10 inches (20-25 cm)|
|14 months||8-12 inches (20-30 cm)|
Guinea pigs at Birth
You would rarely see a pup of guinea pig because they grow very fast. So if you are planning to breed guinea pigs then only you would be able to see a Guinea pig baby. Their size usually depends on the number of pups in the litter, on breed and number of pups in the litter. If babies are more in the litter, the less space they have to grow inside the sow which will affect the size eventually.
Size-wise, a baby of guinea pig will measure around 3-4 inches (8-10 cm) and will weigh around 60-120 grams. The average weight would be 80g (2.8 ounces).
Guinea pig’s Growth
Cavies grow faster and get double in size after just 8 weeks which can around 6-8 inches (15-20 cm). After first weeks, their growth will get slow but will still get around 8-10 inches (20-25 cm) in another eight weeks.
Cavies will reach 8-12 inches (20-30cm) by 14 months and this is when they are considered to be matured. They might continue to grow a bit once they reach a particular age.
Adult Guinea pig – Male/Female
The size would vary according to the breed of an adult guinea pig. Typically, boars are 25-30% larger than sows in both weight and size. They are likely to grow to the breed’s maximum length. If you have a boar, then it will have size range from 8-12 inches (20-40 cm) and weigh around 2-2.6 pounds (900-1100 g).
As females/sows are smaller and lighter in weight than boars, you can easily normally tell if that pig is male or female. If you have a sow, then your fluffy piggy might have size around 8-12 inches (20-25 cm) and weigh around 1.5-2 pounds (700-900 g).
How to measure/ size to know age?
You can measure your guinea pigs size easily by this method.
Put your guinea pig on a flat surface and place a ruler or measuring tape running parallel to its body. Now take a measurement from its nose to rear. You can get a rough idea through this as sometimes guinea pig moves a lot and makes it difficult to work with.
Now you can guess your Guinea pigs age if you don’t know it yet by having an idea about its size.
Caution: don’t buy a cavy which is too young to be sold.
Size depends on breed / largest breed
Normally guinea pig breed doesn’t have a big size variety so it’s hard to say that their size depends on their breed. However, there is a breed which is known to be larger among all of the breeds which is The Rex.
Despite their name they don’t look like dinosaur. The Rex is similar to Teddy guinea pig breed except a little bit bigger in size and denser in coat. They can grow up to 17 inches (43cm) which is 5 inches more than normal size. Though its not necessary they would become this long.
Types of breeds
After reading all of the above information, you have an idea about guinea pigs size, maturity, and growth you must agree that their size depends on various factors and not just one. But still a typical size of a guinea pig is 12 inches (30 cm).
Now, mature guinea pigs need a big space to live in so please make sure you them enough room to live and move around. Also don’t forget to measure your Guinea pig size and weight to determine their health. Early diagnosis can help a lot so best of luck and take care of your little fuzzbutt!