At What Age Will My Cat Stop Growing?

Stephanie Dube Dwilson

Once you've adopted a cat or kitten, your world will never be the same. This cute little ball of fur will bring you joy and memories to last a lifetime. Before long, your kitten will grow into a cute and awkward teenage cat. Later, he'll develop into a more mellow but adventurous adult full of play and snuggles. At what age can you expect your cat to stop growing? Every cat is unique, but there are some general guidelines to clue you in to how big your kitten will get and at what age he'll be fully grown.

Some Kittens May Reach Their Full Size in 12 Months

How quickly your kitten reaches his full size depends on how big he is going to get. The bigger his breed, the longer it will take him to be fully grown. Kittens typically stop growing by the age of 12 months.1 However, larger breeds like Maine Coons can take up to two years to reach their full size. Growth typically slows significantly after 12 months, with a fast growth spurt occurring in the first eight weeks.2

It's worth noting that most cats will reach sexual maturity before they are fully grown. This is similar to a teenager going through puberty, which happens when a kitten is six to nine months of age.3 Around this time, you might consider spaying or neutering your cat. A male cat can father kittens before he's fully grown, and a female cat can get pregnant before she's fully grown as well.

A Kitten's Growth Milestones

You can expect your kitten to experience the following general growth milestones, although the exact age can vary a bit from cat to cat.4

  • 7 days: Their eyes are open, and their weight has doubled to eight ounces.
  • 21 days: They weigh close to 15 ounces. They walk fairly steadily, and their teeth are coming in.
  • 6 weeks: They clean themselves, and they stalk and pounce. At this point, they may weigh a little more than a pound.
  • 8 weeks: Some may weigh enough to be neutered, and many can be adopted.
  • 3–4 months: In this period, they may weigh around three pounds and get up to seven pounds.5 Their adult teeth start to come in (a process usually finished by six months).
  • 4–9 months: They reach sexual maturity.
  • 1 year +: They're fully grown.

Feeding Habits Change as Your Kitten Grows

Some experts recommend free-feeding kittens once they are weaned and eating solid food, so they can get as much food as they need when they're growing. If free-feeding isn't something you'd like to offer, feed your kitten four times a day with about a half cup of food at each meal. Then, when they're around six months old, you can slow down their feeding to about three times a day.7 After a year, you can reduce that to two meals a day. Of course, you should talk to your veterinarian about what schedule and type of food are ideal for your growing kitten.

How Big Will Your Cat Get?

How can you tell how big your kitten will become once she's finished growing? Some experts suggest looking at your kitten's weight at four months of age and multiplying that by two to get your cat's approximate adult weight.8 This is just a ballpark estimate, not a guarantee. Or you can look at your cat's parents to get an idea of how big your cat will ultimately grow to be.

You can also make an estimate based on your cat's breed. A Maine Coon can grow to be 10 to 25 pounds.Munchkin cats will be among the smallest.

Keep in mind that you cannot guess your kitten's future size based on the size of her paws. This is a commonly repeated adage, but no verifiable scientific evidence supports the claim. While a larger bone structure might sometimes indicate a larger cat, it's by no means certain.10

Don't Overlook Your Cats' Emotional Growth

A lot of changes are happening in a kitten's body while he's maturing and growing. While you may be concerned with how fast your kitten is growing and how big he will get, you also want to remember that his emotional and mental health is equally important. Kittens become socially mature after about six to seven months, so the time leading up to this is essential.11 Your kitten needs a lot of socialization. You want to pet him a lot and play with him often. Create fun games between the two of you that he looks forward to every day, whether you play with feather wands, try clicker training, or let him chase you around the house. You also want to have friends over to visit, so your little furball is familiar with people in general and not just you.

Comfort Zone Calming Diffusers can help your kitten be less nervous and stressed while he's learning socialization skills and maturing. These release a vapor that mimics your cat's pheromones, signaling in his own language that your home is safe and secure. Or, consider snapping a Comfort Zone Calming Collar around his neck, and your kitten will take those calming feelings with him as he roams your home. These calming solutions can help your kitten feel safe, happy, and calm.

Kittens grow into adult cats faster than you might expect. They can be fully grown by the time they're a year old, and that time goes by really fast. So make sure you enjoy every minute of it. Take lots of pictures, but more importantly, dedicate quality time to playing with your kitten and deepening your bond.

1. Pet MD Editorial. "At What Age Are Cats Fully Grown?", 30 September 2019,

2. LeBeau, Denise. "When Do Cats Stop Growing? Here's When Cats Reach Their Full Size." Catster, 23 January 2020,

3. Coila, Bridget. "When Is a Kitten Considered Fully Grown?" The Nest,

4. Alley Cat. "How Old Is That Kitten? Kitten Progression: At-a-Glance.",

5. LeBeau, Denise,

6. Pet MD Editorial,

7. Ibid.

8. Parker, Emily. "How Big Will My Cat Get and When Is It Fully Grown?" Catalogical,

9. Ibid.

10. Davis, Jen. "Will the Size of a Cat's Paw Determine How Big the Cat Will Be?" The Nest,

11. Paws Chicago. "How Cats Age." PawsChicago,org,