Four kitten looks out from a basket

Find out how old is your cat in human years.

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How old is my cat in human years? Find out with our cat age calculator

By Natasha James Content Writer

Updated on the

Interested in how old your cat is in human years? Our quick and easy cat age calculator will tell you how old your kitty is (and a whole lot more besides!).

You may have heard that one year of a cat’s age is equal to seven human years (the same is said of dogs, too). So, a three-year-old cat would be 21 in human years. But, this old adage isn’t actually true.

There are various possible sources for this old saying but it’s thought that, whether a marketing gimmick or not, it was simply a way of establishing that a pet’s lifespan is shorter than a human’s.

Scientists and animal behaviourists actually have a far more accurate way of calculating a cat’s age in human years…

How do I calculate my cat’s age in human years?

The updated calculation is fairly simple. It looks something like this:

  • Year one – approximately 15 human years
  • Year two – An additional nine years
  • Each subsequent year – around four human years

So, if your cat has just celebrated their second birthday, they are around 24 in human years. Cat just celebrated their seventh birthday? Then they’re around 44.

“How old are cats in human years?” chart

Want the specifics for your cat? Check out our handy chart.

Cta age calculator: How old is your cat in human years?© Wamiz 

What is the average life expectancy for my cat?

Nine lives aside, cats can live for a long time. The average lifespan of a cat is around 15 years (longer than their canine counterparts) but many cats can live for much longer. It’s not unheard of to meet cats who are well into their 20s and even 30s.

Of course, you can never predict how long an individual animal will live but you can choose a breed with a particularly long life expectancy such as a Siamese or a Manx cat.

How can I tell my cat’s age?

Many people won’t know the exact birth date of their cat. Whether you’ve inherited a cat or adopted a moggy from a shelter, you may be curious to know how old they are. Here are four ways, you can get a better idea of how old kitty is:


For both dogs and cats, teeth are a great indicator of age. A kitten’s first teeth will emerge between two and four weeks of age with their permanent teeth developing somewhere around the three to four-month mark. By 6 months of age, a cat should have all of their permanent teeth and have lost all of their deciduous (or baby) teeth so aging a kitten can be fairly accurate.

But, what about older kitties? As cats age, the staining and plaque build-up on teeth will give vets and animal experts an indicator of old a cat is. But, as pet parents are increasingly cleaning cats' teeth, this method should be taken as an indication rather than an exact science.


Male cats begin reach sexual maturity around five months of age. He may begin spraying and marking his territory to let you know he’s of age.

The average female cat will have her first heat or cycle somewhere between five and 12 months old and can become pregnant and give birth from around 7 months onwards. From vocalising, marking her scent and swelling, you should easily be able to spot when your cat is in heat.


Kittens have super soft baby fur which will thicken and grow more coarse as they age. Just like humans, older cats may develop patches of grey or white fur.

The effectiveness of a cat’s grooming can also be a good indicator of age. Cats are fastidiously clean creatures but their personal grooming routine may become more lax as they age due to arthritis and weight gain.


When a cat reaches senior status, their eyes may become cloudly and experience tearing or even discharge. A healthy young cat, on the other hand, will have bright clear eyes.

The final word

The way you care for a kitten will differ to how you care for a senior cat. A kitten may require jabs, neutering and lots of entertainment to prevent them from scratching the furniture while a senior cat may require a specific diet and plenty of relaxed belly scratches. But, what we can say for certain is, no matter how old your moggy, they’re sure to be a wonderful companion animal.

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Frequently asked questions

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