Most rabbit owners will bring home “baby bunnies,” also known as kittens, at around six to eight weeks old when they can be completely independent of their mother. A common question many owners have is what weight will a rabbit be at different ages?
Depending on the rabbit’s breed, you can determine at what age they will be their full size, and what that full size should be. Some rabbits, despite their breed, may have different growth patterns, which is a result of their individual genetics, diet and living environment.
Taking your rabbit to the vet for a wellness visit after they arrive home is important to make sure your new pet is in good health. The vet can also give you a rough estimate of your rabbit’s age if you’re unsure – maybe you adopted your rabbit from a rescue, and the age is a mystery.
Determining how big your rabbit will grow may determine what breed is right for your family. It may also dictate how much space your need for your friend and how much food you need to prepare to feed your rabbit. If you’re living in pet-friendly housing, the ultimate weight of your bunny may determine if you’re even allowed to live there!
Newborn bunnies (kittens) may weigh between 1-1.5 oz on the lower end of the spectrum. Larger breeds (Giant breeds) can weigh almost triple that.
To put it in perspective, a traditional pencil weighs roughly 1 ounce. Kittens begin to open their eyes at around 7 days and open their ears at around 12 days. If you see baby bunnies covered in fur, you can safely assume they are at least 9 days old. If you happen to be walking along and come across baby bunnies, you may be able to tell their age by a quick glance at these features.
How much weight can I expect my rabbit to gain as it grows?
From 8 weeks to 8 months, an average rabbit can gain anywhere from 0.5 to 0.75 lbs/month – more in larger breeds (and less in dwarf breeds).
Keeping track of your rabbit’s weight can help not only gauge if the amount of food you’re supplying your rabbit is appropriate but also catch any sudden intentional increase or decrease in weight, which should be investigated with the help of a veterinarian. Naturally, their weight may fluctuate, but a few pounds of change without significant change in their diet or exercise should raise a red flag.
Rabbits gain 90% of their adult body weight in the first four months of life. Depending on the breed of rabbit, your bunny could nearly be done with their growth in a few months or just be starting a nearly year-long process of maturation. This can also determine if your bunny is on the right track to reach its full adult weight, if it’s falling behind, or if it’s way ahead of schedule. It could just be that your bunny genetically may end up being smaller or bigger than average. Your veterinarian can help you determine if you should be concerned about your rabbit’s weight and may suggest you keep a log of monthly or weekly weight gain in addition to the amount of food your rabbit is consuming daily. Pay extra attention to what your bunny is actually eating versus the amount you’re feeding them! In the wild, rabbits will continue to eat when food sources are available. So it should be a sign to you if your rabbit is leaving more and more food “left over” from their meals.
Rabbit Weight by Breed
The American Rabbit Breeders Association Standard of Perfection compiled a list of average breed IDEAL weights in ranges of pounds at full-grown adult size [Source]. That being said, mixed breed rabbits or rabbits from pet stores (that may not be purebred) may vary in weight. Don’t panic if your rabbit does not fall within these ranges, as they are just average values. If you do plan to compete with your rabbit in show, you may need to adhere to these weights. If you have concerns in that area, contact the organization that’s affiliated with the competition directly, as standards may differ between groups.
For example:
Aside from the General Body, the Weight Limits for the Mini Lop according to the ARBA Standard of Perfection is as follows:
- Senior Bucks – these are Lops 6 months and older with a weight of 4.5 to 6.5 pounds
- Senior Does – these are Lops 6 months and older with a weight of 3 to 6 pounds
- Junior Bucks and Does – these are Lops under 6 months with a weight of 3 to 6 pounds
As you can see, these are precise weight ranges for a specific breed of a certain age and sex. Here, does (females) have a lower and wider weight range versus bucks (males) which have a more narrow but higher weight range.
So are you still trying to figure out if putting your bunny on a scale will help you determine its approximate age?
Here are 11 examples of different rabbit breeds and their approximate weight at their full size!
Dwarfs 2-3 lbs
- Netherland Dwarf 2 to 2-1/2 lbs
- Himalayan 2-1/2 to 4-1/2 lbs
- Jersey Wooly 3 to 3-1/2 lbs
Most dwarf rabbits are fully grown by 6 months old. If your bunny is supposed to be 8 weeks old and already weighs 2 lbs, chances are he/she may not be a dwarf after all. If you are adopting a bunny that you have been told is an adult dwarf and is roughly 2 lbs, chances are the bunny is a fully grown Dwarf rabbit. It may be hard to determine an exact age from weight alone, but you may be able to tell the rabbit is at least 6 months old if it weighs 2 lbs.
Netherland Dwarf rabbits are one of the most popular dwarf rabbit breeds. They make great pets for small spaces. They also have a substantial life expectancy of roughly 10 years. The downside to these tiny tots is that due to their genetics that make them so small, they sometimes pay the consequence in medical issues. Malocclusion and respiratory disease occur at a higher rate in these rabbits than average-sized rabbits due to the potential risks associated with having a small mouth and a shorter nose [Source].
- Two pounds is roughly 2 packages of butter (4 sticks in each)!
Small 3 ½ – 5 lbs
4. Dutch 3-1/2 to 5-1/2 lbs
5. Lop, Mini 4-1/2 to 6 lbs
6. Chinchilla, Standard 5-1/2 to 7-1/2 lbs
7. Belgian Hare 6 to 9-1/2 lbs
| Age in Months | Weight in pounds |
| 1 | 0.56- 1.06 |
| 2 | 1.06-1.56 |
| 3 | 1.56- 2.06 |
| 4 | 2.06- 2.50 |
| 5 | 2.50- 2.81 |
| 6 | 2.81-3.06 |
| 7 | 3.06- 3.25 |
| 8 | 3.25- 3.37 |
| 9 | 3.37- 3.49 |
| 10 | 3.49 + |
For Mini-Lop rabbits, the average age when they reach full body weight is around 10 months. As you can see by the chart, the average bunny will gain about half a pound a month and then start to slow down as they get closer to 10 months of age – which is the end of their growth period [Source].
- Five pounds is equal to one 2-liter bottle of soda!
8. American 9 to 12
Medium 8 – 10 lbs
9. New Zealand 9 to 12 lbs
In a longitudinal study of the growth of the New Zealand White Rabbit, it was recorded that a study group of rabbits met 72% of their 34-week weight by 16 weeks [Source]. That being said, on the higher end of the spectrum, your bunny should weigh roughly 8.64 lbs, and on the lower end should weigh 6.48 lbs by 4 months of age.
Large 10-14 lbs
10. Lop, French 10 lbs and up
Giant 15-20lbs
11. Flemish Giant 13 up
- Fifteen pounds is roughly the weight of a 40-inch LED TV!
Flemish Giant rabbits are usually born at about 3-4 oz, and by 8-9 weeks, they weigh 5 lbs [Source]. They will continue to grow and gain weight until 14 months of age on average. They live about 4-6 years (and uncommonly up to 8 years +) and can have a length of up to 2.5 – 3 feet long! These giant rabbits are more likely to become overweight than regular rabbits if not exercised properly. Due to their size, they often are more susceptible to pododermatitis, also known as sore hocks. If you plan to keep a giant rabbit as your pet, make sure their living accommodations are not only spacious but comfortable with soft plentiful bedding or soft surfaces where they can rest.
When should I be concerned about my rabbit’s weight?
At the end of the day, once your rabbit is fully grown, the years don’t make that much of a difference.
A three-year-old and four-year-old rabbit will be pretty much identical, especially if they are the same breed and have been cared for in a similar fashion. Once a rabbit reaches the ages of 6 years old and up, they are approaching their senior years of life (which is also dependent on your rabbit’s life expectancy).
You may notice they don’t do as much self-grooming, and their coat can become messy and lack its original luster. You may see your energetic bunny slowing down and not having the usual pep in their step. They may not require as much exercise and may naturally lose some weight through the natural aging process and loss of muscle mass. You may need to supplement their food or change their food to make chewing and digestion easier.
An extreme amount of weight loss, regardless of age, should be of concern, and the rabbit should be checked over by a veterinarian to rule out something more sinister going on.
On the other end of the spectrum, it’s important to recognize when a rabbit may be younger than you originally thought. This could require you to change their diet, and they may need more routine veterinary care.
Rabbits of a certain age shouldn’t be introduced to certain foods and may need supplementation to maintain the healthy gut bacteria they would have normally gotten from their mom. That being said, you should absolutely avoid buying a rabbit under 6 to 8 weeks of age due to not only the medical risk factors but the ill effects of taking the baby away from the mom too early.
So, can you determine a rabbit’s age by their weight alone?
It’s not a perfect science… If you know your rabbit’s breed, you can probably estimate how old or young they are based on their current weight. If you don’t know your rabbit’s breed, the better thing to do is to maybe keep a track of their weight every other week or every month.
You‘ll notice when their weight isn’t increasing as much week to week. That should indicate that they are reaching their maximum weight and the end of their growth phase.
Every rabbit is different, just like every person has a different growth trajectory based on their genetics and their environment. If you have certain limitations to how big or heavy your rabbit can be, it may be best to go through a breeder or have a reliable source of information like registration papers.
Knowing how big your rabbit will get can be important to ensure you can care for your pet appropriately. There are a few additional exam findings your vet can perform to help give you a better estimate, but even they cannot be exact.
So get creative, and you may find a new hobby tracking your rabbit’s weight on a cute chart or taking pictures of them next to the same-sized tennis ball every week! Being prepared to own your rabbit for the next decade comes with a lot of preparation, and the last thing you want to do is expect a 3-pound rabbit and end up with a 13-pound giant! If you can be flexible and don’t mind upgrading your enclosure to house a bigger bunny, then all is well! However, if you really can’t afford to be flexible when it comes to your rabbit’s size, it’s best to do your research and find a reliable breeder/owner/rescue who can ensure you don’t have too many surprises down the road!
