Cat years made simple
Cat Age Calculator
Convert your kitten or cat's age into human years, then explore what that age usually means for growth, behavior, care, and life stage.
Choose your cat's age to see an estimate.
Cat years do not work like a simple times-seven rule
Cats grow very quickly in the first year. A one year old cat is often compared with a teenager, while a two year old cat is closer to a young adult. After that, the common estimate slows down to about four human years for each cat year.
That is why a 2 year old cat and a 12 year old cat should not be compared with the same simple multiplier. Kitten Years uses a more useful estimate for quick answers, charts, and individual age pages.
Start with your cat's age
Explore monthly guides from 1 month to 12 months old.
Look up a cat's age by year, from 1 to 25 years old.
Understand mature, senior, and super senior cat ages.
A friendly estimate, not veterinary advice
The calculator is for general understanding. If your kitten is very young, your cat is older, or you notice changes in appetite, weight, litter box habits, breathing, grooming, movement, or behavior, a veterinarian is the right person to ask.
Common questions
How do you calculate cat years?
This site uses the common 15-9-4 method: the first cat year is about 15 human years, the second year brings a cat to about 24 human years, and each year after that adds about four human years.
Is the cat age calculator exact?
No. It is a helpful estimate. Health, genetics, lifestyle, indoor or outdoor living, nutrition, and veterinary care can all affect how a cat ages.
Do cats need a breed-size calculator like dogs?
Usually no. Cat age estimates are generally less dependent on size than dog age estimates, so this calculator keeps the process simple.