Cat Age Calculator: Cat Years to Human Years
How old is your cat in human years? Enter their age or birthday to convert cat years to human years using the chart vets use. You'll also see their life stage and care tips. Or switch it round to find your own age in cat years.
Your cat
Coat colour (just for fun)
Your age
Find out how old you'd be if you were a cat.🔒 Everything is worked out in your browser. Nothing is saved or sent anywhere.
To save a PDF, choose "Save as PDF" as the printer. It includes the details you entered and the result.
How to convert cat years to human years
Cats grow up very fast at first, then age more slowly. Vets use this rule:
- First year: 1 cat year ≈ 15 human years. By their first birthday, a kitten is about as grown-up as a teenager.
- Second year: add about 9 human years, so a 2-year-old cat ≈ 24.
- Every year after that: add about 4 human years.
Formula for cats aged 2 or older: human years = 24 + (cat years − 2) × 4. For example, a 6-year-old cat is 24 + 4 × 4 = 40, and a 12-year-old cat is 24 + 10 × 4 = 64 in human years.
How to convert human years to cat years
For people aged 24 or older, cat years = (human years − 24) ÷ 4 + 2. So a 40-year-old would be (40 − 24) ÷ 4 + 2 = 6 cat years, and a 60-year-old would be 11 cat years. Under 24, use the chart: 15 human years is 1 cat year, and 24 is 2.
Cat age chart: cat years to human years
Cat life stages
These stages follow the life-stage guidelines vets use for cats. Each one comes with its own needs, and its own fun.
Frequently asked questions
Is one cat year equal to seven human years?
No, that's a myth. A 1-year-old cat is closer to a 15-year-old person than a 7-year-old, because cats mature very quickly. After the age of 2, they age at roughly 4 human years per year, not 7.
How accurate is this cat age calculator?
It uses the standard chart vets use, so it's a good guide. Every cat is different, though. Genes, diet, weight and whether a cat lives indoors all affect how they age, and your vet can tell you most about your own cat.
How long do cats live?
Many cats live to 12–18 years, and plenty reach their 20s. Cats kept indoors usually live longer than those that roam outdoors. According to Guinness World Records, the oldest cat on record, Creme Puff from Texas, lived to 38.
How can I tell how old a rescue cat is?
A vet can estimate a cat's age from their teeth, eyes, coat and muscle tone. Kittens can be aged quite precisely by their teeth. For adult cats it's a best guess, so pick a birthday that matches and celebrate it.
Do indoor and outdoor cats age differently?
Their bodies age the same way, so the conversion to human years is the same. Indoor cats tend to have longer lives because they face fewer risks such as traffic, fights and infections.
How do I help my cat stay healthy as they get older?
Regular vet check-ups, a healthy weight, dental care, fresh water and daily play make the biggest difference. Older cats also appreciate soft, warm beds, low-sided litter trays and food and water within easy reach.
This calculator is for fun and general guidance only. It isn't veterinary advice. For questions about your cat's health, please talk to your vet.