How Fast Do Cats Grow?

Learn about the stages of your cat's growth
How Fast Do Cats Grow?
Francisco María García

Written and verified by the lawyer Francisco María García.

Last update: 22 December, 2022

As opposed to humans, cats grow very fast. At six months they can reach adult size, and can begin to run, jump and even hunt. At that age, humans can’t even begin to walk. Today, we’ll answer the question, “How fast do cats grow?”

From the time they are born, kittens purr to let their mothers know that they’re being fed and are doing well. They do the same thing to let their owners know that they are comfortable and happy.

Cats grow when they begin to walk

This is a black cat eating.

Cats don’t walk well until they are 17 days old. During that time they get around by dragging themselves. When their mother wants to take them to another place she grabs them by the back of the neck with her mouth.

By instinct, the kittens keep still so that they don’t hurt themselves. The first teeth break through their gums when they are two weeks old.

Between the ages of 3 and 4 weeks, kittens grow and can take care of themselves and are able to use the litter box. This is the time to be cautious about their first illnesses.

When between the ages of 4 and 8 weeks, kittens begin to be weaned and start to eat solid foods instead of milk. They are now able to jump, run, climb, and have a good sense of balance. They can clean themselves, as well as their little siblings.

Between the ages of 8 and 12 weeks is a very fun time for kittens and their owners. At this age, cats grow a lot and have the same muscles as an adult feline. However, they still have to learn to calculate heights, speeds and distances.

When cats become adults

When cats are between 3 and 6 years old, we’ll begin to notice that they don’t seem to have as much energy as before. They spend a lot of time sleeping and can even sleep up to 14 hours a day. What’s more, they become very territorial.

Cats start to age between 7 and 12 years. They become more sedentary and relaxed. They spend a lot of time resting and will only play occasionally.

The life expectancy of cats is higher than that of dogs and can even reach 25 years of age.

Hunting abilities as cats grow

Starting from one year of age, kittens spend much of their time learning to hunt. People often turn into the target of their hunting games. After one year of age, most kittens continue growing, but at a much slower pace. They keep growing until they are at least 18 months old.


Sexual maturity in cats, which is puberty in feline terms, takes a few months from start to finish. This process begins when a cat is between 6 and 9 months old. Although a female can become pregnant once she is physically mature, pregnancy can be very hard on her body, which is still growing.

Male cats that have reached this age are fertile. Therefore, it’s not a good idea to keep male and female cats together.

It’s best to speak to a veterinarian about the best age to sterilize a cat. Many veterinarians prefer to spay or neuter kitties before they reach sexual maturity. Neutering males before 6 months of age can avoid undesirable behavior.

Adult cats become social animals

An orange cat sleeping on a cat bed.

At 6 months, a cat grows and becomes more needy or temperamental due to hormonal changes that take place in the body. 

Since a mature cat is an adult, its nutritional needs change. They need a variety of foods, and at around 12 months of age need food for adult cats. We may have to give less food per day after the first year, especially if the cat is sterilized.

If we notice that the cat is developing an enlarged tummy, it’s best to reduce the quantity of food she is given.

In the case of stray kitties, it’s always more difficult to adopt an adult cat than it is to adopt a kitten.

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.