Cat years to Human years: How to determine your cat’s age in human years

Knowing the age of your cat is important because it determines things like what vaccinations they receive when they should be spayed, and how to…

Knowing the age of your cat is important because it determines things like what vaccinations they receive when they should be spayed, and how to best care for them as they age.

Figuring out cat years to human years is easy if you want to jump to our simple-to-use chart click here.

four cats in a basket

To determine how old your cat is in human years there are two things you should do:

  1. First, determine your cat’s age (if you don’t already know it)
  2. Use our cat age chart to determine your cat’s age in human years

How do I age my cat?

cat sleeping

Many owners come into my clinic with cats or kittens that they have found on the street or adopted and are unsure of their age. In this case, here are four things you can look for when trying to age your cat.

What to look for when aging your cat

  1. Weight: Yes, the weight of your cat can help you determine the age of your cat
  2. Teeth: Looking at your cat’s teeth is the most telling sign of your cat’s age
  3. Fur: feeling your cat’s fur can also clue you into their age
  4. Eyes: You can see if your cat’s eyes have some cloudiness which may indicate they are a bit older

Keep these things in mind when trying to determine the age of your cat

  • It is usually a ‘guesstimate’. There is actually no way of knowing for sure the exact age of your cat, but you can get pretty close in age if you know what to look for. Aging cats is easier in younger kittens.
  • Of course, you can always get a second opinion from your veterinarian and they can give you a guesstimate as well.

If you want to know more about aging your pet and what to look for you can read our latest article about determining your cat’s age. In this article, we go a lot more in-depth as to how to age your cat and the signs to look for that come with age.


How old is my cat in human years?

Now that you know approximately how old your cat is in cat years, let’s see how old that would translate to in human years.

Although you might think that cat years are close to human years or on par with the older adage of 1 year to 7 years for humans, many experts say that these numbers are extremely off.

As a rule of thumb, most experts agree that the first year of your cat’s life is equivalent to 15 human years, the second is equal to an additional nine years, and every year after increases by four human years.

Experts state that a one-year-old cat is close to a 15-year-old human’s age and a two-year-old cat would be close to a 25-year-old human.

After two years of age, cats age about four human years for each cat year. So a three-year-old cat would be about 29 years old in human years!

Per The Cat Bible, the author Tracie Hotchner states that a 1-month-old kitten would be equivalent to a 6-month-old human baby and a 16 human years would be 84 in cat years 

CAT BLAND DIET
CAT YEARSHUMAN YEARS
1 Month6 Months
3 Month4
6 Months10
1 15
225
329
433
537
641
745
849
953
1057
1161
1265
1369
1473
1577
1681
1785
1889
1993
2097
21102
22106
23110
Cat Years in Human Years Chart @thepetsdigest

What is the average lifespan of a cat?

cat looking out of the window

Most indoor cats can live well beyond the age of 18 as the average lifespan of most indoor cats is 15 years.

The oldest known cats are a 35-year-old Burmese and a mixed breed cat named Creme Puff, that lived to be 38 years old.

There are several factors that determine how long your cat will live:

  • Breed: While not a rule, there are some breeds of cats that have been known to live longer like the Burmese which tends to have an average life span of 18 years, Siamese, and Savannahs.
  • Lifestyle: Indoor cats tend to live longer than outdoor cats since they are usually better taken care of when it comes to vaccinations and predators. Outdoor cats have a higher chance of being unvaccinated and therefore contracting life-threatening viruses like FIV (Feline Immunodeficiency Virus) and FELV. In addition, outdoor cats run into more predators and other cats that may not be too friendly. The average life span of a cat that lives indoors is 15 years versus one that is outdoors which has an average life span of 7 years.
  • Diet: Feeding your cat a high-quality, healthy diet can help increase their lifespan as well.
  • Activity level: Make sure your cat has a good active life to ensure that it is long
  • Weight: Keeping your cat at a healthy weight will help them live a long healthy life and decrease their chances of having diabetes
  • Diseases: Staving off preventable diseases like FELV and diabetes will go a long way at keeping your cat healthy and hopefully extending their lives. This means keeping their vaccinations up to date, are at a healthy weight, and eat a beneficial diet.