When Do Kittens Stop Growing? Growth Stages Explained
Everything you need to know about a kitty’s growth timeline, including nutritional needs.
In This Article:
When Do Kittens Stop Growing? Newborn to Two Months Two to Six Months Six to 12 Months Main Factors That Influence Growth How to Tell if Your Kitten Is Done Growing
No one is in a hurry to see their kitten grow up, but understanding a kitten’s growth stages can play a big role in their healthcare, nutrition, and exercise needs. It’s important to remember that each kitten will progress at their own pace, but generally speaking, most kittens stop growing and reach their adult size by 12 to 18 months of age. Of course, there is going to be some variation, mainly based on breed.
Let’s look into when kittens stop growing and define those important growth stages, so you’ll know what to expect — and when — from your developing kitten.
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When do kittens typically stop growing?
Most kittens fall into the 12- to 18-month-old category for reaching their adult size. This means by the time they’re about one year old, your kitten will likely reach their adult height, though they may continue to put on weight — hopefully not too much — for a few more months.
Stage 1: newborn to two months (rapid early growth)
The time between birth and your kitten’s first two months is a busy one. This is the time they’re growing the fastest and making the most dramatic changes. Picture it: A kitten is born deaf, blind, and barely mobile. They get through life by feeling for their mother and siblings. By the end of two months, they’re playful, independent, and ready to move to a new home. There’s a lot happening in those eight short weeks.
Their ears and eyes open by two weeks.
A kitten’s baby teeth come in between three and six weeks.
Their mobility will rapidly increase.
They will eat solid food by four to six weeks.
Weaning is in full effect at six to eight weeks.
During this time, you won’t have a lot to do: The mother will be taking care of the kitten’s nutritional needs. But this is a good time to get them used to a little human interaction. Don’t overdo it, but a little handling will get both the kitten and mother comfortable with other relationships. Toward the four-week mark, you can start offering them solid food, increasing the amounts as your kitten nears two months of age.
Stage 2: two to six months (main growth phase)
Though this isn’t the stage for your kitten’s most rapid growth — a lot of growing is still occurring. Your kitten will seemingly change by the week in both size and personality. They will be full of energy and curiosity. Socialization is key during this time. You should expose your kitten to as many different situations as possible to help prevent anxiety and encourage them to better navigate change. This is also how they learn to interact with other animals and humans.
A lot of muscle and bone growth is taking place, so ensure they get plenty of exercise to make them strong and prevent injury.
Their first vet visit and vaccinations can start at six to eight weeks.
Feed them a kitten-specific diet.
Schedule their spay/neuter around the five to six-month mark.
Stage 3: six to 12 months (typically stops growing)
Most cats will reach sexual maturity between four and six months old. That means there may be some changes in their appearance and behavior if they aren’t spayed or neutered. Their growth rate will dramatically decrease to a point where you may not notice many changes, but they are still happening. Your kitten will slowly increase in height and weight, and their activity levels may start to decrease.
Most cats will stop growing around 12 months of age.
Transition them to an adult diet as the one-year mark nears.
See your veterinarian every six to 12 months to encourage lifelong health.
Main factors that influence how long kittens grow
A kitten’s growth rate isn’t set in stone. Many factors can influence this, including breed, nutrition, and overall health.
Growth differences by breed
While we don’t see the major variations in size between breeds that we do in dogs (such as a Chihuahua vs. a Great Dane), some cat breeds are smaller or larger than others. This is important because generally, the smaller the adult size, the sooner a kitten stops growing, and the larger the adult size, the longer it takes to get there.
Smaller breeds, such as Cornish or Devon Rexes, may reach their mature size before 12 months of age, while larger breeds, like Maine Coons, can continue to grow for two or even three to four years. What we would consider regular-sized breeds, such as Siamese or Shorthairs, will stop growing around their first birthday.
Genetics definitely are at play here, too. Even within a specific breed, you’ll see smaller and larger cats. If a kitten’s parents are larger, they’ll likely be larger (and vice versa).
How nutrition affects growth
Growth and development are contingent on proper nutrition. If a kitten is given a high-quality diet, they are more likely to reach their mature weight, while kittens who are deprived of nutrients tend not to reach their full growth potential. Feeding your kitty a kitten-specific diet is important to ensure they get the proper nutrients (in the right amounts) to ensure normal growth.
Overall health
Illnesses during kittenhood can affect a kitten’s growth. You may see smaller-than-predicted sizes if a kitten is impacted by infections or parasites during any growth stage.
How to tell if your kitten is done growing
Because a kitten’s growth rate slows down after six months of age, it may be difficult to recognize changes. This is where monitoring comes in. Regularly weighing or measuring your kitten will show you when their growth has stopped, because these numbers will no longer change much. Along with numbers, you may also see:
A regulated appetite (your kitten may stop eating everything in sight)
Body proportions evening out (your kitten will lose their lankiness)
Activity levels possibly leveling out
Growing takes a lot of energy, so when it stops, cats may find themselves with a surplus of calories. Monitor your cat’s weight carefully to make sure they aren’t gaining excess weight and adjust their diet accordingly.
Bottom line
Kittenhood is a time of intense growth and development, with most cats stopping their growth around a year of age. This year is divided into three main growth stages defined by specific physical and behavioral differences, which are important in determining a kitten’s nutritional, health, and exercise needs. Growth rates can be affected by breed, genetics, health, and nutrition.
References
“2021 AAHA/AAFP Feline Life Stage Guidelines.” Journal of Feline Medicine and Surgery. 25 Feb 2021. https://pmc.ncbi.nlm.nih.gov/articles/PMC10812130/#section3-1098612X21993657opens in new tab.
