How To Tell A Chinchilla’s Age


Chinchillas and people have a lot in common when it comes to ageing. We go through similar life cycles and age patterns and it is even possible to tell a chinchilla’s age just by observing it.

There are signs that will show you just how old a chinchilla is, like the state of its fur, the shape of its body, its activity level, etc. A chinchilla’s age can be even “converted” into human years and you would be surprised just how old they get.

As chinchillas grow to adulthood, they get bigger and puffier at their prime years and then, just like people, they start to grow thinner, with hair and weight loss, gaining a calm demeanor. 

Summary of today’s article:

How To Tell How Old A Chinchilla Is

Size – grown chinchillas weigh on an average between 1-2 pounds but they can be heavier, as they reach old age it is not uncommon to see weight loss.
Activity level – chinchillas are very active and bouncy pets when they are young and even in their adulthood, although older chinchillas tend to be more tame and less active. Read this post to find out more about how much a chinchilla should weigh.

Body tone – chinchillas are “equipped” with strong lean muscles and almost no body fat, as chinchillas get older they start losing their muscle mass and become more frail.

Fur – chinchillas are known for their luxurious fur, which is also a sign of proper care and good health, but as they get older, their fur becomes less dense and they could shed a lot. 

Behavior – young chinchillas are very curious, fast and they can show a little aggression and irritability, while older chinchillas are naturally more calm and complaisant.

aged chinchilla

Chinchilla Age In Human Years

You would be surprised by how old chinchillas are when compared to human years. By observing the growth and behavioral patterns of chinchillas, veterinarians were able to establish an age correlation table, which would be equivalent to human age.

According to this table, a 6-month-old chinchilla is 12 years old in human years. A 5-year-old chinchilla is equivalent to the human “midlife crisis” age of 45 years. With most chinchillas living to be around 10 years old, the age would convert to a cozy 78 years in human age.

Chinchilla Age In Human Years

In addition, if you are lucky enough to own a chinchilla that is 15 years old or older, you are in the blessed presence of a centenarian with 123+ years in human age. So if you get a chinchilla while it is still very young you will experience all of the growth stages with your pet and in a span of 15 years you will have a baby, a teenager, an adult and an old guy all in just one little chinnie.

With a proper environment, nutrition, exercise and love, most chinchillas live long, healthy and happy lives. The Guinness record holder for the oldest recorded chinchilla is a little guy from California, USA, named Radar who was just a few months shy away from his 30th birthday, a record in human years that is yet to be achieved.

Chinchilla Growth Stages

A chinchilla’s gestation period (the forming of the fetus until birth) is around 111 days. Newborn chinchillas are called kits and they are born with both eyes open, covered in fur and very active, ready to take on the world. 

At such a young age their ears would be flat against their head, as if they are wearing tiny earmuffs. 

By the age of 3 weeks the baby chinchillas’ ears will start to prop-up and this is when they start resembling more like their parents, but much smaller in size. 

With the age of 6-8 weeks, the kits will start eating solid foods on a regular basis but they will still depend on their mother’s milk. 

The weaning period is over by the age of 12 weeks and the chinchillas are no longer depending on their mother’s milk. 

After being separated from their mother at the age of 12 weeks up until the next period of almost 6 months chinchillas are considered juveniles, although from the 8th month they are also considered to be “mature”. 

Chinchillas are considered adults when they reach 1 year of age, although many of them may continue growing up until they are 2 years old.

Chinchillas reach sexual maturity at the age of 8-12 months, but the earliest can be at 4 months and at this stage, it is not recommended to breed chinchillas. 

READ :  Can Chinchillas be Emotional Support Animal?

Female chinchillas will show signs of being in heat and ready to mate such as a more irritable or even aggressive behavior, although other females might become more submissive in this period, urine spray and a fur slip is quite common to appear during this period.

The chinchillas you buy from a pet store or adopt from a breeder are usually at least 4 months old, but can be a year old as well. The size of the chinchilla will indicate its age because chinchillas that are 4 months old are still very young and will continue to grow while in your care.

Chinchilla Size By Age

Chinchillas are capable of having a litter of babies anywhere from 1 to 6 kits, although the most births are usually with 1 or 2 kits. The size of the babies will depend on the number of kits within a litter, a big litter will have smaller babies vice versa.

When they are born, baby chinchillas weigh anywhere from 1-2 ounces and they are just a little bigger than a golf ball. Each day they gain weight and grow rapidly.

Chinchilla's size by age

By the age of 8 weeks, a chinchilla will weigh around 7-8 ounces and will be about a third of its adulthood size.

Adult chinchillas weigh between 1.1-1.8 lbs and grow to the size of around 9-15 inches without counting the tail, which adds another 4-6 inches. Female chinchillas tend to be larger than males, although this can vary due to genetics and breeding.

Signs Of Old Age In Chinchillas

Chinchillas can age at different rates so it might be possible for a younger chinnie to show signs of “old age” which is completely normal and depends on the character of the pet. As a chinchilla gets older, it will become less active and quieter.

The playtime could be interrupted with multiple breaks as they get tired more quickly, even though they will start off their playtime with as much spunk as a younger chinchilla would. The playtime could also become visibly shorter as your pet will enjoy its private rest time more.

An old chinchilla might change its habits to suite its new needs like avoiding the top shelves and its favorite hammock and hanging out more often in its comfortable hide box on the ground level of the cage where he would not be required to move a lot or jump. 

Older chinchillas will shed and can appear more frail. At this point, it is very important to provide proper nutrition to an aging chinchilla as it will lose weight due to a loss of appetite and possible dental issues. 

As with old age, there might be an onset of age-related illnesses such as cataracts, dental problems, arthritis and weakened immune system. 

Dental Issues

As chinchillas get older, they tend to chew less, which can result in dental issues and overgrown teeth, this is why you should encourage chewing with fresh hay and new chew toys. With an irregular chewing and eating pattern the chinchilla’s immune system might be compromised and as such the chinchilla would be susceptible to bacterial or fungal infections.

At this stage, you should provide the highest quality pellet and hay, which would be packed with all necessary nutrients to help your pet stay healthy. 


Arthritis is a common age-related illness in chinchillas so they should be handled with care in order to avoid the possibility of your pet falling and hurting itself. Arthritis can be treated in chinchillas and your veterinarian will provide proper medication for this ailment, which will minimize the pain and maximize the movements of the joints.

Unlike arthritis, cataracts are unfortunately not treatable, but they thankfully cause no harm or discomfort to your pet and it can still live a comfortable old-age life.


It is hard to accurately age a chinchilla without knowing any background information or date of birth. Even though we have multiple signs to look for in old chinchillas, they are not the proven norm and there are many chinchillas who will not show signs of aging right up until they pass away.

These chinchillas act like younglings their entire lives and live up to be 15 years old or more. 

No matter how old your chinchilla is it will always depend on your love and care, and it will always enjoy your company. Every chinchilla should get the optimal conditions to reach very old age and we certainly wish all of them do and hope that you and your chinchilla enjoy each other’s company along the way.

  • Facebook
  • Twitter
  • Google+
  • Linkedin
  • Pinterest
It is main inner container footer text