How old do Cats grow?


If this is the first time you have a kitten as a pet, you will surely have many doubts. How old does a cat grow? It is probably one of the first questions that came to mind.

And in this post we will help you with this, we will clarify this doubt, but you will also learn a lot about them.

When cats are small, they are undoubtedly very adorable little creatures, full of curiosity and energy. As the days go by we will notice that the kittens begin to grow, very quickly.

Cats, unlike humans, are fast growing. In just a year or less they reach their adult size, within this period they begin to run, jump, hunt.

They go from weighing just 100 grams to 2 or 3 kilograms. They even reach sexual maturity within this first year of life.

It is important that you know that the growth of cats happens in different stages, in which they go through notable physical changes, they will even have changes in their characters and behaviors.

And then we will talk a little about all this, so that you are able to recognize each of these stages of growth of a cat.


Growth of a baby cat

As mentioned before, cats go through different stages of growth after they are born and before they become adults. Let’s see how old baby cats grow up to.

Although it is important to know that the growth time pattern is not exactly the same in each cat, there are some that grow slower, and others that grow faster.

This varies according to the breeds of cats. But if there are certain similarities in their growth, which can be classified into stages. 

When the kittens are newborn (first stage) they usually weigh between 85 and 120 grams and in the first week of life they usually double in weight.

In these first weeks of life, kittens are totally dependent on their mother, therefore, it is very important not to separate them from hershe will know how to keep them warm, nourished and clean.

Kittens are born toothless, blind, deaf and with a slight sense of smell, with which they will be able to recognize their mother’s scent.

Week 1

At birth, breast milk is very important, that they consume it. The first milk that its mother produces is known as colostrum, it has a special composition, it contains a large proportion of immunoglobulin’s , that is, it transfers the necessary antibodies to the new born kittens for the correct development of their immune system.

The little kittens when they arrive in the world also have very limited mobility. All they will be able to do is a very weak meow.

Week 2

Between days 9 and 14 the kittens begin to open their eyes and unfold their ears. This is where a transition period ( second stage ) begins. 

Apart from beginning to see and listen, they will also begin to try to mobilize themselves to explore what surrounds them as they can, their gait will be unstable, they will even begin to crawl, and it will not be until approximately 17 days when they will walk more or less well.

Generally when their mother wants to move them from one place to another, she will take them with her mouth from the nape of the neck. In addition, she will be in charge of defending them when necessary during these stages. It should also be noted that from week 2 their teeth begin to come out.

It is also during this stage when they become aware of the other members of their litter, and begin to compete for their mother’s nipples, the time to eat.

Week 3

Already in week three ( third stage ) the kittens have a very well developed sense of smell, their ears fully raised, although the sense of hearing is not so developed.

As their teeth begin to come out, they must learn to control the force of their bite, so as not to hurt their little brothers with whom they can already play too much.

It is also during this stage when they will no longer depend so much on their mother, she will no longer be as attentive to them as when they are born.

Because they are already able to digest their food and relieve themselves.

It is also in the third week when the kittens can begin to be weaned, they can already be given solid foods, such as canned.

Week 4 onwards

Kittens begin to become more independent, and this is where they can be taught to relieve themselves in a litter box. The kittens will also be much more skilful, they will start to run, play and explore their surroundings with a lot of energy. This happens in weeks 4 and 5 of your life.

After this, it is the ideal time for each kitten to begin to have contact with humans and other animals in general ( fourth stage ).

They should take them gently, pamper them so that they gain confidence and associate good deals and positive things with the contact of people. It can be said that the eighth week is the ideal one to adopt them or put them up for adoption. 

Of course, you have to be aware that this is a very active stage in cats. They are usually too playful and funny. And maybe your furniture will regret it.

Cats between 8 and 12 weeks have grown and will continue to grow, they already have the same muscles as an adult cat, of course, not so strong and they still have to learn well to control themselves and measure distances, speeds and heights.


How old do male and female cats grow?

Between month 3 and month 6 , the cat will already be in a stage where it will not need its mother at all. Now it will be able to survive on its own, it is practically prepared to reach adulthood without major complications.

It is also likely that you already want to leave the house. We can define this as the juvenile period ( fifth stage ).

It is during this period when the cat, both the female and the male , reach their final shape and size, they become like young adults, that is, their size begins to stabilize.

Of course, before becoming fully young adults they face puberty, which is when female cats begin to go into heat, female cats between 5 and 8 months and male cats between 6 and 7 months.

The puberty of cats and very similar to the puberty of humans, they tend to be rebellious, to disobey, to do what they want.

Now, when they finally become young adults, they tend to be a bit calmer, although their desire to play is still quite high, kittens are still very active.

But how old do ordinary cats grow? Usually they finish growing after six months, maybe sooner, and sometimes until after it all depends on the breed. Oh, and of course, after this time they can continue to gain weight.


How old do purebred cats grow?

As we mentioned earlier, the growth of the cat will vary depending on the breed, since there are cats that reach a larger size than others, therefore, some take longer to grow than others.

Although in most the growth period does not exceed one year. For example, there is the Maine Coon breed of cats , they are a giant species of cats, they can take up to 4 years to finish growing. On the other hand, there is the British breed which takes 3 years to grow.

The European Common Cat can take up to 2 years to reach its final size. And other breeds like the Persian Cat and the Siamese Cat, take about a year. 


When does a cat reach adult size?

After the sixth month of life, the cat reaches adulthood ( sixth stage ). It is at that stage, there is no longer so much rebellion, they are much calmer and more mature.

They will sleep a long time, but nevertheless they will still be very playful. And you will realize that they are nocturnal animals, as they are more active at night.

If you want them to sleep at night, find a way to play with them during the day, keep them active. And well, in response to the question ” until what age do cats grow “, we can say that a common cat reaches its adult and definitive size at one year .

Between 3 and 7 years of age, the cat will no longer have the same energy as before, and will sleep much more and will be much more territorial .

Already between 7 and 12 years old, our kitten is getting old, and every time it will be much less active and lazy, it will very seldom want to play. The life of a cat can last up to 20 years.


Weight of a cat by age

The weight of cats varies by breed, there is a lot of difference in weight according to age between cats of small, medium and giant breeds.

But, if average weights can be established according to the type of cat that is being analyzed.

Next, we give you an average weight in cats according to their age.

  • Newborn cat : 100 grams
  • 2-3 week old cats : 170-225 grams
  • Cats 4-5 weeks : 225-450 grams
  • 8 week old cats : 680-900 grams
  • 12 week old cats : 1.3-1.5 kilograms
  • 16 week old cats : Approx. 1.8 kilograms
  • Cats 18-24 months : 3-4.5 kilograms (depending on the breed)

Quality of life of a cat: A good diet

It is very important that a kitten has a good diet so that it can overcome each stage of its life in a healthy way.

A good option to offer a healthy and balanced diet to our cats is to use commercial food.

There are very good quality feed , they offer all the necessary nutrients for a good diet.

Now if you have enough time to prepare the food yourself , ( Barf Diet ) you can do it, but first you should consult with a specialist who helps you put together a suitable menu.

But you must bear in mind that these cats are carnivores, they need a lot of proteins (necessary for hair, skin, nails, tendons, ligaments and cartilage) and fats (they provide the necessary energy for our cat) to be well fed.

You can opt for feed and canned. The feed is a dry food, which offers a balanced diet, (not all, although it is true).

It may be the most comfortable option for us, but it is good that you observe the composition and know how to distinguish when we are dealing with a quality food.

In case of illness or obesity , the cat will also require a special diet, recommended by your veterinarian. Consult him.

Canned food is a moist, tasty and appetizing food for them . It is good to combine wet foods in your dry diet. This way they will have less periodontal diseases and less tartar.

Very well, we have already reached the end of this post, how could you see, cats are little animals that grow very quickly , in just one year they are capable of reaching their full size.

Sure, these go through various stages before. I hope the information we gave you about ” how old do cats grow ?” be of great use to you. If you have something to contribute you can leave your comment, we would love it.


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