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Kittens, all wide eyes and wobbly paws, can also wield surprisingly needle-sharp teeth and claws during their biting and attacking phase, and it may seem as if they'll never grow up. Then, in the blink of an eye, your little fur baby becomes an adult.
So, which is it? Are they forever tiny terrors, or do they truly transform in a flash? Understanding that journey from tiny terror to grown-up companion isn't always intuitive, but knowing your cat's stage of growth can help you gain valuable insights into their specific nutritional, sleep, and exercise requirements, ensuring you're providing the best possible care as they navigate each fascinating phase of development.
The Growth Stages of a Cat
A cat goes through a lot of changes in their lives which can be marked by specific growth stages.
The Kitten Phase (Birth to ~6 months)
The most significant physical changes happen during the kitten phase, as cats go from a blind, barely mobile dependent to a feisty ball of energy that is near maturity. During their first six months, kittens undergo a remarkable transformation, rapidly gaining weight, developing coordination, and experiencing significant bone and muscle growth. Their playful pounces and clumsy explorations are all part of this crucial development
Kittens in this phase are absorbing all sorts of information from their environment. They will play anytime, anywhere, and are growing and changing quickly, but they’re not done growing yet! Knowing how to care for a kitten requires a multifaceted approach.
During this stage, kittens should be eating a high quality kitten food that provides high levels of protein, fats, and specific nutrients such as DHA. How much you feed a kitten will depend on the food they’re eating and their activity level, so check the label on the bag for a starting guideline. They will need to sleep often and will play for short bursts. Though they may not seem like it, kittens are ripe for training during this phase, so be sure you’re teaching proper litter box technique, what they can and cannot play with, and getting them used to a schedule.
Adolescent Phase (6 to 12 months)
Around that six month mark, most kittens will start their final slide to adulthood. Sexual maturity typically occurs between five and seven months of age which can bring on some changes in behavior. Most veterinarians will recommend having your cat spayed or neutered around six months to avoid unplanned pregnancies. Know what to expect after a cat spay or neuter, which could include sluggishness or weight gain, but remember that these teenagers are often still very active and growing, though at a slower pace.
As they transition into adolescence, cats begin to assert their independence, exploring their surroundings with more confidence and refining their social skills through interactions with other household members or pets. To ensure your increasingly independent cat maintains good manners, focus on consistent socialization during this phase. This involves regularly exposing them to various people, gentle handling, and different environments in a positive way.
Continue feeding kitten food until your kitty starts to approach one year of age and then you can start the transition to an adult cat food. Females tend to stop growing during this phase, reaching their adult size by about 10-12 months. Males often take a little bit longer.
Adult Phase (1+ Years)
We’ve finally reached the age when a cat is fully grown. Some males and big cat breeds will continue to grow until they are 18-24 months old while the majority of cats will stop growing by their first birthday.
But just because your cat has stopped growing doesn’t mean they’ll coast smoothly through adulthood. They will require a high-quality food for adult cats, plenty of exercise, socialization, and mental stimulation. They also need regular veterinary care to help prevent health issues.
When Are Cats Fully Grown?
You may hear that cats are fully grown by one year of age, but that’s an oversimplification. There is plenty of variation around that number based on sex, breed, and even whether a cat is spayed or neutered.
Most female cats and smaller breeds will reach full size by 10-12 months of age, while male cats can continue to grow until 12-18 months. Large breeds may even keep growing until they’re two years old.
What does it mean when a cat has stopped growing? It means they have reached their greatest height and length, and they won’t continue to get any taller or longer. Weight can change throughout a cat’s adult life, so it’s not as good of an indicator.
Key Factors that Influence Feline Growth
How big a cat will get depends on a lot of different things, some of which you can play a part in.
Breed and Genetics
Your cat’s genetic composition has a lot to do with when they will stop growing and how big they’ll get. For example, Maine Coons are big cats. Their DNA codes them to grow bigger and slower than most other cat breeds. Smaller cats, such as Munchkins, will be very small cats that reach their adult size at a much younger age.
Nutrition and Diet
Even though genetics may lay the groundwork for when a cat stops growing, they also need the right tools to finish the job. Proper nutrition is essential for a cat to reach their full growth potential.
Without the right number of calories, fat, protein and a proper balance of vitamins and minerals, your kitten’s growth may end sooner than genetically planned. Providing kitten food until a cat stops growing will help ensure they have what they need. If you have any questions about when to transition your cat’s food, speak to your vet.
Health and Environment
Your cat’s blueprint for growth also assumes they aren’t dealing with any concurrent health issues. Illnesses and injuries can derail your kitten’s development. Also, not getting enough exercise or dealing with stressors, such as living outdoors, can alter your kitten’s path as well. Spaying and neutering can delay the closure of growth plates, meaning your kitty could continue growing for slightly longer than they would if left intact.
All of these factors can feel a little overwhelming, so be sure to include your veterinarian in your kitten’s journey to help ensure they stay as healthy as possible to reach their full growing potential.
Do Male Cats Grow Differently?
As with a lot of species, male cats tend to grow larger than females do, and as with most species, larger animals tend to grow for longer. So, it would make sense that most male kitties don’t reach their mature size until later than their female counterparts. Females are typically done growing around one year of age, while males can take up to six months longer.
Here’s the deal: males have a higher concentration of the hormone testosterone, which is responsible for increasing muscle mass, among other things, which takes time. The difference in size between male and female cats usually isn’t huge, but males can be a bit taller, longer, and heavier, especially if they’re intact.
How does neutering fit into a male cat’s mature size? Well, remember earlier when I told you that spayed and neutered cats tend to grow longer due to a delayed closure of the growth plates? That’s still true, but intact males have the growth benefits of testosterone on their side, which can increase their overall muscle mass. In short, males that are neutered may still grow tall and long but tend to put on more fat than intact males that tend to put on more muscle.
This has led some veterinarians to consider neutering male cats at a later age to allow the testosterone to balance out body mass with muscle mass.
How to Support a Cat Through Their Growth Journey
Your cat is going to do most of the growing work, so you can sit back and enjoy it, but don’t stay completely hands off. You can still take an active part in ensuring your cat is healthy and gets as big as they’re supposed to.
Monitor Their Growth
Alongside your veterinarian, you can make sure your kitten is on a healthy track by regularly weighing and measuring them. This is not only a great bonding activity but can give you a little insight into growth spurts and stages.
Care Adjustments by Life Stage
The big change that growth signals is diet. Knowing when your kitten stops growing is key to switching to an adult diet. Growth can also play a part in the space and activities that your kitten needs. You may need to upgrade your carrier, bedding, or cat trees to accommodate their adult size, and their grooming and enrichment preferences may change as well.
Preparing for a Fully Grown Cat
Your adult cat is going to change in size as well as behavior from that of their kittenhood. Hopefully, you’ve planned your cat’s space appropriately to make sure there’s room for their adult bodies, but you’ll also need to adjust their food and activity. Once your cat reaches their adult size, they don’t need the extra energy required for growth and their activity levels may drop as well. To keep them from gaining weight, adjust their food as necessary. If you need help deciding your cat’s proper weight, body condition scoring will help. Your veterinarian can also give you insight and help you find good activities and enrichment that can help maintain a healthy weight as well.
Why Pet Insurance Matter for Growing Cats
Watching your tiny kitten grow into a curious adolescent and then a fully-fledged adult is one of the most rewarding parts of pet parenthood. At Embrace Pet Insurance, we understand that this incredible journey of growth comes with its own set of potential bumps in the road.
Kitten Phase: During their rapid early development, kittens are particularly susceptible to common issues like upper respiratory infections, which can easily lead to unexpected vet visits costing anywhere from $150 to $500 depending on severity.
Adolescent Phase: As they become more adventurous, adolescent cats face a higher risk of injuries; for example, treating a more complex fracture from a fall could unfortunately result in veterinary bills ranging from $500 to $3,000 or more, potentially including surgery and aftercare.
Adult Phase: Even after reaching their full size, adult cats can still encounter unforeseen illnesses like a sudden urinary tract infection, which might incur costs ranging from $250 to $750 for diagnosis and treatment.
Embrace is here to offer a safety net throughout all these stages, helping to alleviate the financial worry of unexpected vet costs so you can always focus on providing your beloved cat with the best possible care and ensuring their healthy development every step of the way. Get pet insurance for cats while your kitten is still young so that you can be protected through all the growth stages.
To further support your cat's healthy growth and well-being, consider adding an optional non-insurance wellness plan. This can help you budget for routine preventative costs such as essential vaccinations during kittenhood, regular parasite medications throughout their life, and important dental care, promoting overall wellness for a healthy future and providing you with additional financial peace of mind.
So, When do Cats Stop Growing?
While all cats grow at their own pace, the majority of them will reach their adult size by the time they’re a year old. Large breeds and males may take a little longer, reaching their full size by 18 to even 24 months of age. Being aware of these different stages, from those tiny, rapidly growing kitten months to the more laid-back pace of adolescence and finally, the confident stride of adulthood really helps us understand how best to care for our beloved companions.
While the journey from that tiny, toothy terror to a fully grown feline might feel like it happened in the blink of an eye, understanding each stage of their development empowers you to cherish those fleeting moments and provide the best possible care along the way.