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How Big Do Chinchillas Get? [Average Size Guide For Owners]

It has happened to many people, you start looking to add a pet to your family, and as you begin visiting stores or searching online, you come across the adorable grey ball of fluff known as a Chinchilla. With any caged pet comes an inevitable question. “How big is this new pet going to get?” Let’s take a look at what size you could expect your Chinchilla to reach.

So, how big do Chinchillas get? Chinchillas come in two different sizes – short and long-tailed. The short-tailed Chinchilla will grow to be between 11 and 19 inches long and weigh between 38 to 50 ounces (2.4 – 3.1 pounds). The long-tailed Chinchilla is a bit smaller, maxing out at 10 inches and weighing between 21 to 28 ounces (1.3 – 1.75 pounds). Either way, Chinchillas finish growing by 2 years old.

It seems quite contradictory, right.

How can the long-tailed Chinchilla be shorter in length?

Certainly an odd one but one that is true nonetheless.

And it is essential to be aware of the differences here.

Besides, long-tailed chinchillas are those often kept as pets and the ones you will likely see in pet stores.

Chances are, you’ll be getting a slightly smaller pet. But as we will soon find out, this doesn’t necessarily mean they require any less space!

Let’s now take a closer look at how important size is to how you will care for your Chinchilla.

What Age Are Chinchillas Fully Grown?

Chinchillas reach their mature length and weight by the time they are one year old. Chinchillas, like many members of the rodent family, are relatively quick-growing animals. By the time you celebrate your Chinchilla’s first birthday, it is considered a fully grown adult!

This doesn’t mean that the weight of your Chinchilla won’t change after their first year of life, but that most of their significant weight gain has passed, and they are probably at their final length.

Pet chinchillas are often fed diets that are higher in calories and more readily available than their wild food sources, which can lead to a bit of extra weight gain for adults.

Very young Chinchillas will stay with their mother and nurse until they are 8-12 weeks of age, during which time they will grow significantly.

After they are weaned, your Chinchilla is ready to come home with you and finish its growth in the next 8 – 10 months.

When your Chinchilla comes home with you, it will look like a miniature version of its adult self.

Some Chinchillas will grow more quickly than others, so don’t be surprised if you notice that your Chinchilla doesn’t grow much after about the 8-month-old mark.

That is completely okay! 

Just like humans, each Chinchilla is unique, and ages for final size will vary slightly.

You can keep track of your Chinchilla’s weight by using a digital scale made for measuring small pets.

Knowing the weight of your Chinchilla will help you to know if it is healthy and happy.

Because Chinchillas have such lovely fluffy coats, it is easy for them to hide weight gain or loss. 

If you weigh your Chinchilla and notice a sudden or unexpected change in weight, especially after they are fully grown, you know it may be a good time to call your vet.

How Much Space Do Chinchillas Need?

The smallest healthy cage size for a single Chinchilla is 2-foot x 2-foot x 3 foot or 12 cubic feet of space. 

Chinchillas are larger than many other rodent pets such as hamsters, rats, and guinea pigs, and in order to stay healthy, they need room to move their bodies freely in their cage without being cramped or harmed.

Chinchillas are active and will move throughout their entire cage on a regular basis.

When considering a Chinchilla’s space, it is important to consider horizontal floor space (at least 2 foot by 2 foot) as well as vertical space.

Chinchillas love to climb and jump, and they need enough space to move their bodies safely both side to side and up and down.

Make sure you have enough vertical room for your Chinchilla to live on multiple levels within about 3 vertical feet of space.

Chinchillas also need space to explore (supervised) outside of their cage.

You should be able to give your Chinchilla plenty of safe opportunities to explore a room of your home from time to time.

Whether you can safe-proof a particular room or whether you invest in a rodent playpen – either work, and either is advised. 

So long as your Chinchilla is safe and cannot escape – that is. 

You will find that your Chinchilla is often most active and ready for play in the evenings and will enjoy being able to hop and jump around without the limitation of cage walls.

Start by letting your Chinchilla out in a small closed-off space to allow for easy catching until they are used to you and your environment.

Being able to move and exercise will help your Chinchilla maintain a healthy size throughout its entire life.

What Type Of Cage Does A Chinchilla Need?

Chinchillas need a metal or wire cage with multiple levels for both their safety and their lifestyle. Metal cages are durable, stand up to Chinchilla chewing habits, are easy to clean, and come in a wide variety of sizes. The sky’s the limit on cage size when purchasing a metal cage for your Chinchilla.

Chinchillas are very active pets, and they prefer a cage that has multiple levels to allow for climbing and jumping.

A cage with levels also allows them to stretch and bend to their full length as they move around.

This ability to move and jump between levels helps them to stay healthy and happy.

Some cages come with adjustable plastic “floors” that you can move up or down to change the height and size of levels within your cage.

Ramps from level to level give your Chinchilla the choice of hopping from place to place or walking.

Chinchillas will want a designated safe sleeping space within their cage. This space needs to be large enough to allow your Chinchilla to curl all 10-19 inches of its body up into a comfy, sleepy ball.

A good size for a Chinchilla hide-out is 8 in. x 8 in. x 5 in. 

This is big enough to fit the Chinchilla’s body and tail while still feeling cozy and burrow-like.

Chinchillas will often use this space if they feel overstimulated by their surroundings or they simply need some time alone.

Another popular option for Chinchillas is a Chinchilla hammock that hangs in the cage, and the Chinchilla can curl up for sleep or quiet time.

This is what it looks like on Amazon if you wanted to take a look.

In order to maintain a healthy weight and stay happy, your Chinchilla may benefit from having a wheel in its cage.

Just as companies make wheels for Hamsters and other pets, wheels are made that are designed for Chinchillas.

You need to consider the Chinchilla’s size when selecting a wheel so that it is large enough for the Chinchilla to comfortably run without over bending its back.

A safe running wheel for a Chinchilla has a diameter of at least 14 inches.

Overall, your Chinchilla needs a cage that it feels is big enough to move about in, that will be durable enough to hold up to any chewing, be easy to clean, and has options for quiet spaces of solitude and exercise.

Dietary Needs For Optimal Growth

Chinchillas are herbivores which means they eat a plant-based diet. As we talked about earlier, Chinchillas do a lot of growing in their first eight to twelve months of life. This means that feeding them a healthy diet is extremely important.

Many places sell pelleted food designed specifically for Chinchillas.

This food has all of the essential vitamins and nutrients a Chinchilla needs to meet its basic growth and nutrition requirements.

Along with pellets, Chinchillas will need access to hay for foraging and occasional fresh vegetables.

Chinchillas as pets do not run as much as their wild counterparts. They also do not have to work as hard to find food.

This means that feeding your Chinchilla the right amount of food for its size is a must. 

Chinchillas who are fed too much pellet food may become overweight and experience health problems.

It is recommended that you give your Chinchilla around 2 tablespoons of pellet food daily and free-choice access to hay.

Don’t forget fresh water is vital for the well-being of any household pet.

What Is My Personal Experience With Chinchilla Growth?

I have owned several Chinchillas over the years and would quickly like to share my personal experiences of them – particularly relating to their size.

My first Chinchilla was just a tiny soft baby when I brought it home. It weighed about 0.5 pounds and easily fit into my cupped hands.

I remember holding it and marveling at both its softness and its miniature size. 

Over the next several months, I made sure to feed my Chinchilla a steady, healthy diet and give it plenty of exercise.

My Chinchilla was long-tailed and ended up weighing right at 1.5 pounds as an adult.

Despite its small size, it had powerful legs that it used for jumping all over its cage and my apartment.

My Chinchilla proved to be sweet and playful and was a perfect companion during my years of apartment dwelling.

Chinchillas: A Small Pet with Big Personality

As you have read, Chinchillas grow quickly to their adult size. You can expect them to be fully-sized around 1 year of age.

When fully grown, they will have either long tails (3-6 inches) or short tails (1 – 3 inches) and weigh between 1 – 3 pounds.

Of course, their exact length will depend on whether you take a short or long-tailed Chinchilla home.

But either way, they are active and need plenty of space to jump, play, and explore. They love multi-leveled cages and these are ideal.

Besides, they take up less vertical space in your home, while affording them more surface area.

And perhaps the best part – Chinchillas can be tamed and learn to enjoy the company of their owners.

So, if you’re considering a Chinchilla as a pet, knowing their size and cage requirements is a great first step towards ownership!