A complete guide to your ferret’s growth.
If you are planning to buy or adopt a ferret, the first question that might come to your mind is When Do Ferrets Stop Growing? After all, you must know about the basic life cycle of a ferret before making it your pet friend.
Ferrets usually live for 5 to 10 years. Hence, it is a no brainer that they will stop growing at quite an early stage of life.
On average, a ferret stops growing between 4 to 6 months. They are also capable of reproducing at this age.
Without a doubt, ferrets make a good pet. Being a ferret owner, you should be careful with the ferret’s growth as they have specific food and nutritional requirements.
Let’s discuss in detail the growth of your ferret, how you can track it and when do ferrets stop growing.
When Do Ferrets Stop Growing?
A ferret will continue to grow at a rapid speed, and then ultimately stop growing at four months of age. They will reach their full size by this time.
A female ferret or jill reaches its sexual maturity between 5 to 8 months and can reproduce at this age. Female ferrets have faster pregnancies with the duration being only between 39 to 42 days.
Male ferrets or hobs achieve sexual maturity at 6 to 8 months.
A three year old ferret is considered to be in its midlife as ferrets grow rapidly.
Lifecycle Of A Ferret
Just as all living beings have a definite lifecycle, a ferret also has its lifecycle. At different phases of life, different terms are associated with the ferret. Your ferret will also show signs of aging as it grows.
Depending upon their age, ferrets show various physical characteristics.
Let’s have a look at the life journey of a ferret.
Classification of Ferrets As Per Their Age
- Baby Ferret or Kit
A newborn ferret is referred to as a kit. At 8 weeks, the weaning process of a ferret starts, and then, just in 2 more months, it develops completely.
- Adult Ferrets
Ferrets reach their full size at 4 months, and from this point, they are considered adults.
Ferrets can either be neutered ferrets or intact ferrets. An intact male ferret is referred to as a Hob, while an intact female ferret is known as Jill.
A ferret is considered to have entered its midlife at 3 years of age.
Physical Characteristics of a Ferret
- Kits
The average weight of kits usually ranges between 10 to 12 grams. Just like other babies, their eyes and ears are closed and they have a slight pinkish body color.
A newborn ferret will start developing small peach fuzz fur on the first or second day.
At 2 weeks, the cute little baby teeth start to appear.
You might be surprised to know that till the age of 3 weeks, the kit is unable to see or hear anything. It is entirely dependent on its mother.
You can expect their baby hair to grow at 4 to 5 weeks of age. During this week, they weigh around 200 to 250 grams. This is also the week wherein they will make an effort and try to explore their surroundings.
Once the kit is around 6 weeks, it tends to open the eyes and ears and see its surroundings.
At 7 to 8 weeks, the ferret starts developing permanent teeth and they can start eating solid food. Once the ferret develops its permanent teeth, it is important to regularly clean it, plaque buildup, and oral infection can occur.
This is the time when usually the kits are weaned and are separated from their mother.
- Adult Ferrets: Neutered and Unneutered
A kit is considered an adult ferret at 4 months and they reach their full body size.
- Male Ferrets
An unneutered male ferret is referred to as Hob. They usually weigh around 5 to 6 pounds. On the other hand, a neutered male ferret weighs around 2 to 4 pounds.
- Female Ferrets
An unneutered female ferret is referred to as Jill. They usually weigh around 2 to 3 pounds. A neutered female ferret will weigh 1 to 1.5 pounds.
Sexual Maturity of a Ferret
A ferret is considered an adult at 4 months of age. However, they achieve sexual maturity at 5 to 8 months.
If you are not looking for reproduction amongst your ferrets, it is best to get them neutered. Breeding ferrets involves a lot of time and it costs a bomb.
When male ferrets are in heat, their scent glands tend to release stink bombs and can become extremely aggressive. Surgical removal of the glands is possible. A vasectomised hob does release stink bombs.
On the other hand, female ferrets in heat will continue to stay in heat till they are bred. This can lead to a dangerous condition called aplastic anemia which can also lead to death. In this condition, there is a shutdown in the production of red blood cells, white blood cells and platelets.
Activity Level of a Ferret Based on Its Age
Kits usually depend on their mother entirely, as they cannot see or hear anything for the first few weeks. Hence, they are busier in exploring the surroundings rather than playing with the owner.
Young ferrets tend to be extremely playful and active. As they tend to get older, about 3 years of age, you may see a drop in their activity level. Their playfulness will decline.
Moreover, older ferrets become a bit rigid with their habits. They might become grumpy if they need to interact with other cage mates and maybe highly intolerant towards other pets like cats and dogs.
However, younger ferrets usually do not have this issue and can be trained as you want.
The Prime of Ferret’s Health
At the 2 year mark, your ferret will be at the peak of its health. They tend to build up strong muscles and great bone density. At 2 years, the ferret’s coat is in the best form.
At What Age is A Ferret Fully Grown?
Ferrets are sexually dimorphic like most mammals. The female ferrets typically weigh less than male ferrets. They are smaller in size as compared to the male partners.
Male Ferrets
Male ferrets or hobs usually stop growing between 4 to 6 months and you can consider them as fully grown. Once they are fully grown, a ferret will weigh around 2 to 4 pounds.
Female Ferrets
Similar to the male ferrets, female ferrets or Jills too are considered fully grown between 4 to 6 months.
They usually are smaller as compared to the male ferrets, and weigh somewhere between 1 to 3 pounds.
Thus, you can consider a ferret to be fully grown between 4 to 6 months.
What is The Ferret’s Average Lifespan?
The average lifespan of a healthy ferret is between 5 to 10 years. It is extremely crucial to feed them the right food as they are obligate carnivores. A healthy diet will lead to a healthy ferret and thus improve its longevity.
You should be extremely careful with your ferret’s vaccinations and routine veterinarian checkups. This is because ferrets tend to develop many diseases, which when detected at an early stage can help to save your ferret.
Below are few major ailments that can affect the life expectancy of your ferret:
Adrenal Disease
Adrenal gland disease is the most common form of the disease that affects a ferret that is greater than 2 years of age. This is related to the early neutering of a ferret that might result in unwanted enlarged adrenal glands. This also leads to an adrenal tumor.
The early clinical signs of the adrenal disease include hair loss, swelling of the vulva in female ferrets, swelling of the prostate in male ferrets, and thinning of the skin.
You should immediately consult your vet if the above signs appear. Most of the time, the medications provided work well by reducing the adrenal stimulation in your ferret.
Canine Distemper
Canine distemper is another contagious disease that can affect a ferret. The affected ferrets show signs like mild conjunctivitis and yellowish discharge from both eyes. Vaccination for this is available and you should provide an appropriate dosage of vaccination to your ferret as per the veterinarian’s recommendation.
Insulinoma
Insulinoma is a tumor that is related to beta cells i.e insulin hormone producing cells of the pancreas. It can occur in ferrets if the ferret is fed with a high sugar content diet. Hence, it is important to closely monitor the ferret food.
What is The Typical Size of a Male and Female Ferret?
Just like many other species, ferrets too are sexually dimorphic in nature. The male ferrets tend to be slightly bigger and heavier than the female ferrets.
An unneutered male ferret or Hob usually weighs around 5 to 6 pounds. On the other hand, a neutered male ferret weighs around 2 to 4 pounds.
An unneutered female ferret or Jill weighs around 2 to 3 pounds. A neutered female ferret will weigh 1 to 1.5 pounds.
The body length of a male ferret is while female ferrets measure around 18 inches.
Apart from the above mentioned differences, both male and female ferrets look the same. They have the same energy level, color, body, and activity level.
Is Your Ferret Growing Properly? Track Its Growth
Considering that the answer to when do ferrets stop growing is 4 to 6 months, it is evident that they do grow at a really fast pace.
A healthy kit will double its weight in the first five days of birth. It will gain weight rapidly over the next few days and weigh around 30 grams which is almost triple its birth weight.
By the third week, their weight multiplies ten times in comparison to their birth weight. A female kit might weigh a bit less as compared to a male ferret.
Kits are considered as adult ferrets at 4 months, and they will achieve their full weight by this time.
The body length of a ferret is calculated from the tail to the tip of the nose. For male ferrets, it will be around 20 inches. Some ferrets even grow up to 24 inches, while shorter ones tend to measure around 18 inches.
Female ferrets measure around 18 inches in length.
It is important to get a ferret cage based on the length of your ferret.

Take a look at the quick comparison table below to get an idea of your ferret’s growth:
Ferret’s Age | Male Ferret | Female Ferret |
Weight of Newborn Kits | 10 to 12 grams | 10 to 12 grams |
Weight at 1 Week | 30 grams | 30 grams |
Weight at 3 Weeks | 100 grams | 80 to 100 grams |
Weight at 16 Weeks | 1000 grams to 2000 grams | 600 to 900 grams |
Length 16 Weeks | Approximately 20 inches | Approximately 18 inches |
Table: Average Weight and Length Measurements of Ferrets
You should note that the above figures are average numbers. Your ferret might have the same statistics.
If your pet ferret is healthy and active, then you should not be concerned if the above figures aren’t met. However, if you feel that your ferret is not active or dull, you can consult your veterinarian.
FAQs on When Do Ferrets Stop Growing?
1. At What Age Do Ferrets Calm Down?
A ferret calms down when he grows old i.e 4 years and above. Ferret are playful little creatures. When they are a kit and young, they will tend to play for hours and always be around you.
However, you can expect your ferret to calm down as he ages. Ferrets 4 years old or above will show less energy. Even though they will be active and alert, they will surely not play for hours.
2. Do Ferrets Recognize Their Names?
Yes, ferrets do recognize their name. However, you cannot expect a baby ferret to immediately recognize its name.
Once a ferret is an adult, he can start learning new things and can even recognize his name.
3. Do Ferrets Die Easily?
Yes, ferrets can die easily without any prior health issues. Ferret might get ill suddenly and die all of a sudden.
Moreover, female jills that are unneutered and cannot mate can also die easily due to lack of mating. The prolonged high doses of estrogen released during the heat can lead to aplastic anemia. This is a serious condition that can cause death.
Conclusion
In conclusion, the answer to when do ferrets stop growing is 4 to 6 weeks. You can consider your ferret fully grown and an adult at this time.
You should keep a track of your ferret’s growth to ensure a healthy ferret.
Both male and female ferrets have almost the same behavior barring minor physical differences. Hence, you can also consider this aspect when you are planning to get a furry friend for yourself.