Cat Years To Human Years: How Old Is My Cat?

Key takeaway

It's a common misconception that one cat year is seven human years. Instead, cats develop quickly in the first two years of their life. One cat year equals around sixteen human years, and two years is around 21 human years. After your cat is two years old, its human year equivalent is closer to four than seven.

Have you ever looked at your cat and wondered how old they are in human years? Indoor cats have an average lifespan of 12 to 18 years, so you might think calculating your cat's human age is easy. Unfortunately, however, you can't divide the average lifespan of a human by a cat's lifespan and get an accurate number for how old your cat is. 

If you're wondering, "How old is my cat?" you'll need to know the formula for cat years to human years. Your cat's age in human years might not be what you think it is. Keep reading to find out how old your cat really is. 

How to calculate cat years to human years

How To Calculate A Cat's Age In Human Years

Most pet parents believe one human year is equivalent to seven cat years. However, this simply isn't true. You'll need to use a more specific formula to find your cat's age in human years. A one-year-old cat is actually much closer to sixteen years of age instead of seven, and a two-year-old cat is about 21 years old.1 After the age of two, cat years are worth four human years, giving us a formula we can use to guess the age of any cat in human years.1 However, there's so much more to understanding your cat's age. To determine your cat's age in human years, you'll need to understand its lifecycle from birth onward.

Kitten phase

Kitten Phase

Pet parents love the young, cute kitten stage that occurs from birth up until a kitten is around six months old. During this time, they grow up fast (literally). You'll see your kitten grow right before your eyes. However, towards the end of this stage, they'll be the equivalent of a ten-year-old human.2

Junior phase

Junior Phase

The junior stage begins at seven months old until your cat is two, lasting a year and a half. During this stage, they're as big as they're going to get, reaching their adult size.2 By the time your cat is done with this stage, they're the equivalent of 24 years old. 

Adult phase

Adult Phase

The cat growth cycle is complete by the time they're adults. The adult phase begins around your cat's third year of life up until they're six years old. At this point, they're fully developed, reaching their full potential in terms of size and health.2 Adult cats are usually in relatively good health as they're fed a balanced diet of cat food developed for their life stage. By the end of the adult stage, your cat is around 40 human years old, reaching the beginning of midlife. 

Mature phase

Mature Phase

Your cat is considered mature from around the 7th year of its life until the 10th.2 This is a cat's middle age, and they may begin to show less interest in play, sleep more, or spend more time alone, depending on their personality. By the end of this period, your cat will be 56 years old. This is also the age at which many cats develop underlying age-related health issues. As your cat continues to age, it's important to monitor their health for signs of illness. 

Senior phase

Senior Phase

Around the 10th year of your cat's life, they're considered seniors, reaching 70 human years and beyond.2 At this stage, one human year is the equivalent of four cat years, so if your cat is 12, it'll be around 64 years old. During the senior stage, you'll need to continue to care for your cat. However, by now, they may have slowed down and no longer feel the need to play. Instead, they may spend more time sleeping. Senior cats are prone to many health conditions, so you'll need to pay close attention to their health and take them to the vet more often for examination to prevent any major illnesses from affecting their quality of life. 

Other Ways To Estimate Your Cat's Age

The easiest way to determine your cat's age is by using the formula we talked about above. Unfortunately, stray cats' ages in human years are more difficult to predict because they've lived in harsher conditions. In addition, stray cats typically don't live as long as domestic cats. However, you may still be able to figure out how old they are. If math isn't your forte or you don't know when your cat was born, there are a few other ways to help you guess how old your cat is in human years, including:

  • Teeth: Older cats typically have stained teeth because most pet parents don't brush their cat's teeth at home. Therefore, the more time plaque and tartar have to build up; the more stained your cat's teeth will be. If there is only some yellowing around the gums, your cat is likely an adult but not yet reaching senior age. Of course, using your cat's teeth to predict their age isn't always effective because different diets can affect the teeth differently. For example, cats that eat kibble may have less plaque on their teeth because the kibble scrapes it away over time. Some cats may also develop tooth resorption, which causes the teeth to break down. In addition, cats with better home dental care will have whiter, healthier teeth and gums. 
  • Eyes: Young cats have clear eyes without discharge, but as they age, the eyes may appear more clouded. Cats with eye cloudiness are typically seniors. However, there are some health conditions that can cause eye cloudiness in any cat's eyes. 
  • Coat: Your cat's coat will change as they age. Older cats typically have courser, less shiny fur. Additionally, cats will get gray or white fur as they age. However, since all breeds have different types of coats, using your cat's coat to determine their age isn't the most accurate option, especially if you know when your cat was born. 
  • Bones: Young cats are more muscular and lean because they have more energy for play and activities like hunting their favorite toys. Older cats are bonier because they lose muscle tone over time and with less activity. 

FAQs

Is 1 year 7 years for cats?

Science has proven that one cat year does not equal seven human years. A one-year-old cat is actually closer to sixteen years old in human years. Different phases of a cat's life can account for different cat-to-human years. A one-year-old cat is the equivalent of a 16-year-old human, while a two-year-old cat is the equivalent of a 21-year-old human. For every year after your cat's second year of life, you'll add four human years. 

What is the average lifespan of a cat?

The average lifespan of a cat is 12-18 years for indoor cats. However, how long your particular cat will live depends on its diet, activity level, and potential underlying health conditions. In general, indoor cats live longer than outdoor cats, mostly because they don't have to fend for themselves and have access to veterinary care when they need it. Outdoor cats can live anywhere from 2-5 years, depending on their location and when they're let outside to live. Outdoor cats are also at a higher risk of developing infections and diseases like Feline Herpesvirus, getting hit by cars, eating toxic plants, or being attacked by predators, which affects their lifespan. 

Of course, if a cat is abandoned when they're seven years old, it'll have a longer lifespan than outdoor cats born as strays. However, you should keep your cats indoors if you want them to live long, healthy lives because you can't control what happens in an outdoor environment. While your cat may want to run around and play outside, it's simply not safe for them, and they can enjoy a full, healthy, and safe life indoors. 

Do female cats live longer than male cats?

Female cats tend to live longer than males, and neutered cats also live longer than those intact. Additionally, purebred cats are less likely to live as long as crossbreeds.3 Of course, this is a generalization. How long particular cats live depends on many factors, so it's important to care for your cat to the best of your ability by providing them nutritious food, plenty of playtime, and having a good relationship with your vet to ensure your cat  always has access to vet care. 

Closeup of middle aged man cuddling with his cat

Final Notes

By now, hopefully, you can easily determine how old your cat is in human years. However, throughout your cat's life, you'll need to monitor its health to prevent potentially harmful and life-threatening underlying illnesses. Feeding your cat a balanced diet, ensuring they get enough exercise, monitoring their weight, and going to your annual wellness visit at the vet is key to ensuring they live a long, happy life. 

Luckily, going to the vet is easier with Dutch. Dutch telemedicine for pets can help diagnose and treat underlying illnesses like arthritis and joint pain that may affect your cat as they age. We can also advise you on how to keep your cat healthy depending on its life stage. Try Dutch today

References

  1. "The Special Needs of the Senior Cat." Cornell University College of Veterinary Medicine, 22 Aug. 2022, https://www.vet.cornell.edu/departments-centers-and-institutes/cornell-feline-health-center/health-information/feline-health-topics/special-needs-senior-cat.

  2. "How to Tell Your Cat's Age in Human Years." International Cat Care, 7 Mar. 2019, https://icatcare.org/advice/how-to-tell-your-cats-age-in-human-years/.

  3. Rigby, Sara. "What's the Longest a Cat Can Live for?" BBC Science Focus Magazine, 16 Apr. 2021, https://www.sciencefocus.com/nature/whats-the-longest-a-cat-can-live-for/.