Cat age calculator
Cat Age Calculator — Convert Cat Years to Human Years
Enter your cat's age and breed to see the equivalent in human years. The calculator uses the standard feline aging curve: cats age roughly 15 human years in their first year, 9 more in the second, then about 4 per year after that. Breed lifespan data helps estimate where your cat sits on the life-stage chart.
How Cat Years Work
15
Human years in year one
A cat's first year equals about 15 human years.
24
Human years by year two
By the end of year two, your cat is roughly 24 in human terms.
~4
Per cat year after that
From age 3 onward, each cat year adds roughly 4 human years.
The First Two Years Count the Most
A cat's first year equals about 15 human years. By the end of year two, your cat is roughly 24 in human terms. This is why kittens mature so fast — they reach sexual maturity around 6 months, which is the human equivalent of early adolescence.
After Year Two: About 4 Human Years Per Cat Year
From age 3 onward, each cat year adds roughly 4 human years. A 7-year-old cat is about 44 in human terms — solidly middle-aged. A 15-year-old cat is equivalent to a 76-year-old person.
Breed Affects Lifespan
Indoor cats typically live 12–18 years, but breed matters. Siamese and Burmese often reach 15–20 years, while larger breeds like Maine Coons average 10–13 years. The calculator factors in your breed's typical lifespan to show where your cat falls on the life-stage chart.
Life Stages Explained
Veterinarians use six life stages. Each stage has different health screening recommendations — senior cats should have twice-yearly vet visits.
Age Is Half the Picture
Life stage tells you what to expect from a cat at a given age; it does not tell you whether the cat is carrying the right amount of weight for that age and breed. The cat weight calculator takes the same breed and age inputs and checks your cat's weight against the range for its breed, including the kitten growth curve.
Age also sets what a cat should look like. The cat breed quiz scores frame size as one of its six questions, so a kitten that is still growing will not match the large breeds yet — re-run it once the cat has finished filling out.