When Do Cats Stop Growing? At What Age Are Kittens Full Grown?

You might think it’d be a simple thing to hazard a guess at what age a cat will reach its full growth potential, finally hitting the point where he or she stops growing; sadly, however – this just isn’t true.

I’m going to sell it to you straight right at the start of this article: there’s no way to tell exactly when a cat will stop growing, or at what age a particular kitten will be fully grown, let alone what size a cat will be once he or she finally has finished growing.

Picture from post Avery’s Baby Pictures

The best we have are approximations and rough guesses, and even then, those guesses are not-so-great considering the age gap is incredibly wide when you’re talking about the ages at which cats are finally full grown. Ah cats: such mysterious creatures, even when you understand them as well as one possibly can.

To top it all off, if you have a cat whose age you’re unsure of, say because you took in a stray like Thomas and I did, the question of when your cat will stop growing becomes even more difficult to hazard to answer – as guessing the age of a cat is, too, not an exact science.

I have firsthand experience with this myself. The first day I took Avery to a vet, Thomas and I asked if Avery was an adult or a kitten, and if he was likely to continue to grow. The vet assured us (he was honestly completely convinced) that Avery was already an adult; full grown, and was already as big as he was going to get. This turned out to be an incredibly ironic statement considering merely a year later when we took Avery back for his annual check up, he was over double his initial length and size. To be fair to the vet, Avery’s turned out to be probably the longest cat I’ve ever met in my life. Needless to say, the vet was shocked at how much he grew past his initial visit.

While this story should show you what you likely already guessed – that you can’t make exact estimates about the age of a cat if you don’t know for sure, and that you certainly can’t guess when or how large a kitten will be when fully grown – I’m here to give you the rough estimates in case you find them helpful anyways. Let’s get into it.

Petlinks Jeepers Creepers Catnip Rat Toy – Amazon / Chewy

When Will My Cat Stop Growing? When Are Cats Usually Full Grown?

So here’s where the wide age variance comes into play:

Cats stop growing anywhere between 6 months and 4 years of age.

Yep, I told you the age gap was enormous. Obviously, I’m going to delve a little deeper because you can get a better estimate than just saying 6 months to 4 years, but just keep this enormous age gap in mind because your cat may in fact be one of the outliers, and not at all the norm when it comes to age full growth is hit.

When Does the Average Cat Usually Hit Fully Grown Status?

At around the 6 month point, kittens slow down substantially in terms of speed of growth. They will often continue to grow past this point, but it is likely to be nowhere near at the rate they had been growing prior to being 6 months of age.

Most cats continue to grow until around the 1 year mark. At around 12 to 14 months, most cats stop growing.

Again, this is true of many cats, but certainly not all. Saying a cat will stop growing somewhere between 6 months and 4 years is a very wide age range to be working with, but you never know when it comes to your specific cat if he or she will fall into the average or the outliers category.

The only definite way to find out, of course: wait and see.

Does Breed Have Anything to Do With When Cats Stop Growing?

A cat’s breed does actually have a lot to do with when a kitten will finally stop growing.

Maine Coons, Ragdolls, as well as some other breeds, do not often hit “fully grown” status until somewhere between the ages of 2 and 4 years. That’s roughly 1-3 years later than the average house cat.

Bengals usually hit full size around year 2, often becoming fully grown somewhere between the ages of 20-30 months, or just over a year old to just under 3 years of age. Again – this is later than the average house cat, though only by around 1-1.5 years.

If you have any experience with the ages a specific cat breed usually hits fully grown, do let me know in the comments section down below.

Are There Ways of Estimating How Large a Cat Will Be Before a Cat is Fully Grown?

Sadly, since it’s not even possible to know for sure if your cat has finished growing, it should come as no surprise to you that it’s impossible to determine how big a cat will be once it has fully grown.

That doesn’t stop people from trying, however!

I’ve seen rumours around the net suggesting if you look at a cat’s paws, you might be able to use paw size to make a reasonable guess to determine whether your cat will still grow or whether he or she will be a small or big cat once full growth is reached.

Supposedly, if your cats paws are very small, your cat may not have much growth left in him or her. If your cat has big paws and is still fairly tiny, he or she may have plenty of growth time and growth size left in him or her.

Not sure how accurate this estimation technique is, but I thought I’d share! Let me know if you’ve ever heard of this rumour, if you’ve ever tried it yourself, or if you’ve any other tips for estimating a cat’s full-grown size before he or she hits it.

When Did Your Cats Stop Growing?

Would love to know if you’re reading this and have cats of your own: when did your cats stop growing?

Have you plenty of experience with cats besides housing your own little felines? Ever worked in a shelter, at a vet’s office, or fostered kittens? What age do you feel the average cat hits “fully grown” status?

Have experience with a particular breed over others? What breed do you have a lot of experience with and, in your experience, at what age does that breed usually come to be fully grown?

Love to hear your thoughts in the comments below!