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It’s more than likely that no matter how much time passes, our cute little kitten will always be a baby in our eyes.

But… until what age is our cat a kitten? At what age is a cat an adult? When do cats stop growing?

Cats go through various stages during their growth, changing enormously, both physically and in terms of maturity and temperament.

Each stage is unique and in this article we will tell you about it so that you finally know at what age an adult cat is!

The 6 Stages of Growth in Cats

Cats go through several stages before becoming adults. Although experts differ in their criteria to know what these stages are and especially when they start and when they finish exactly, it is possible to differentiate 6 fundamental growth stages in cats :

  • Neonatal period from birth to 9 days of age: The neonatal period begins after birth and ends around 9 days of life. The kitten, as soon as it is born, is very thin and has not yet opened its eyes. At this stage, he is guided by touch and smell, his locomotor system is limited and he depends completely on his sire in order to survive.
  • Transition period from his 9 days to 14/15 days: from 9 days to 14 or 15 days after delivery, during which we will observe that the kitten begins to gain in mobility and autonomy. At this stage, the kitten opens its eyes and ear canals.
  • Socialization period from 2 weeks to 7/8 weeks: once the 2-week candle is blown out, the kitten will start to consume additional food to the mother’s milk, he starts to be more independent, to run and play non-stop with his brothers and sisters, these games will be based on chasing each other and biting. It is at this time that a fundamental step begins: the kitten’s socialization. It is considered more than important at this age that the kitten comes into contact with other animals, other people, so that he can get used to creating bonds with different people, which will allow him, in the future, to develop a more sociable and friendly character. This stage ends around the 7 or 8 weeks of life.
  • Juvenile period from 7/8 weeks to 6/7 months: this is when the cat reaches its final size and shape, officially becoming a young adult. Normally, they begin to be quieter, although they still stand out for their delirious desire to play and be active. Thus, to answer the question formulated in this box at what age a cat reaches its adult size, we see that it is at this stage of life that their size begins to stabilize. Depending on the breed, it will take a while for the cat to stop growing, and it is also at this age that sexual behavior begins to appear, moving on to puberty.
  • Puberty: around 6/7 months the males reach puberty, while the females reach it between 5/8 months. This stage resembles the typical adolescence that can be observed in people because it is a period of rebellion, during which the kittens will only do as they please.
  • Adult age: Once this critical period of rebellion is over, our cat will adopt his definitive character, being completely mature, balanced and quiet.

By going through the different stages of cat growth, we see that a cat reaches its adult size from one year old, however, it is only around the age of three years that a cat is adult because its character and temperament will finally be balanced.

When Do Cats Stop Growing According to their Breed?

Although in general the growth of all cats is similar regardless of breed when compared to other species, it differs when compared between different breeds of cats.

For example, giant cats, like the Maine Coon, take up to 4 years to reach their adult size.

It is the same for British cats, which are slow growing, reaching, on average, their adult size around 3 years old.

On the contrary, as you can imagine, the small cat breeds finish their growth well before the big cat breeds, they represent the average for cat growth. For example, Siamese and Persian cats finish their growth around one year old, while the European cat can grow up to 2 years old.

How Do I Know If the Kitten Is at the End of its Growth?

Weigh him every week, if for 1 month his weight every week has not moved, then he is at the end of his growth.

This weight reached at the end of growth should be a reference for the rest of his life.

Indeed, the adult cat can be brought to gain weight, especially after sterilization and it is thus necessary to take care that he does not grow too much and to keep in mind his reference weight.

Does Sterilization Stop the Cat’s Growth?

Did you know: sterilization is not an obstacle to good growth. Your cat, even if it is spayed or neutered at the age of 6 months, will continue to grow until it reaches its adult size.

No current study has shown a significant influence of the age of sterilization on the final size, whether the cat is sterilized very, very young (before three months) or much older (at puberty). Even after sterilization, especially at a very young age, your cat continues to grow to adult size.

However, it is not recommended to sterilize kittens that are too young, even if technically the operation is perfectly feasible as soon as the kitten reaches 2 pounds of weight, that is to say a little before its two months of age, because certain behaviors would be modified.

At What Age Does a Cat Become Calm?

Generally speaking, kittens are more active and playful than adult cats, although it all depends on the character of each cat, as well as the characteristics of their breed.

Generally speaking, cats are more likely to spend their days playing without stopping as soon as they reach one and a half to two months of age and they will only stop around 6/7 months of life, this being the period during which the kitten is most active, almost hyperactive.

Nevertheless, our cat will keep his desire to play until about his first year of life, then he will start to calm down and play less.

Although we have just said that cats calm down around 1 year of age, it is important to say that the majority of cats like to play for most of their life.

Therefore, it is very complicated to say precisely at what age a cat calms down and no longer plays because some of them play until old age.

The important thing is to always offer them different toys to keep them entertained, as well as scratching posts located at different heights.

Kitten Photo by birgl from Pixabay

About the Author

Skye

A girl from Scotland who's in love with cats! I love to share tips on how to take care of our beloved furry friends.

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