If you’ve ever watched a kitten grow up, you know how fast it happens. But when exactly does a cat stop growing? There is no single answer to this since cats grow at different rates based on their breed, nutrition, gender, and individual genetics.
Still, we can look at a few different guidelines to give us a good idea of when your kitten can be considered a full-grown adult.
Stop Googling - Ask a Real Vet
Content:
At What Age Do Cats Stop Growing
For most cats, growth slows down and stops around 12 to 18 months of age, but certain breeds take longer. Large breeds like Maine Coons or Ragdolls can keep growing until about 4 years old.
One Reddit user summed it up well, saying, "It depends on the breed. The largest breeds can keep growing for 4 years. Most cats probably stop around 1-1/2."
Veterinary studies, such as those by Dr. Ellen Kienzle, show that larger breeds take longer to reach full size than smaller ones.
Research suggests, “Larger British Shorthair Cats took longer to reach their mature weight than the smaller Exotic Shorthair Cats.”
To give you a general idea, here’s a table showing at what age different cat breeds generally stop growing:
| Breed | Age at Full Size | Characteristics |
|---|---|---|
| Domestic Shorthair | 1 to 1.5 years | Average size |
| Siamese | 1 to 1.5 years | Slim build |
| Maine Coon | 3 to 4 years | Large size |
| Ragdoll | 3 to 4 years | Large size |
| Bengal | 2 years | Muscular |
| Sphynx | 1 to 1.5 years | Hairless |
| Savannah | 2 years | Tall, exotic |
Remember, using a Petcube Cam can help you track your cat’s growth and behavior changes during these important years.
Read more: How Long Can You Leave a Cat Alone?
When Is a Cat Considered an Adult
A cat is typically considered an adult once it has finished growing (so between 12 and 18 months or so), although this age can vary. But this can be misleading because simply no longer growing does not necessarily mean an animal is really an adult.
To show you what I mean, we need to consider how our kittens develop. It's helpful to separate physical growth, sexual maturity, and mental maturity.
Sexual maturity in cats usually happens between 5 to 9 months of age, which means a cat is capable of reproduction, but it does not mean they have stopped growing or become adults (which is why an ethical breeder will not breed a cat at this age).
Physical growth continues well beyond this stage and, for most cats, slows down around 1 to 2 years. Also, mental maturity, or when a cat reaches full “adult” behavior and temperament, can take a bit longer, typically settling by the time they’re about 2 years old.
So, while your cat may stop physically growing within the first year or two, they may not reach full adulthood in terms of maturity until later. Think of it like teenagers who have reached their full height. They may no longer grow any taller when they reach a certain age, but it will still be a few years before they mature into real adults.
Read more: How To Introduce a Kitten to a Cat and Make Them Get Along
Conclusion
Most cats will stop growing by about 18 months, though larger breeds may take longer. Watching for changes as your cat grows can help you make sure they stay healthy, and tools like the Petcube Ply 2 make it easy to check on them anytime.