Cat Age Calculator
How old is your cat in human years? Enter your cat's age for an accurate conversion.
How is cat age calculated?
Cats mature very rapidly in their first two years. Year 1 is equivalent to approximately 15 human years, year 2 adds 9 more (24 total), and each year after that equals about 4 human years. Unlike dogs, there is no significant size variation in cat aging.
This formula is based on guidelines from the International Cat Care organization and is widely used by veterinarians worldwide.
Frequently Asked Questions
How old is a 1-year-old cat in human years?▾
A 1-year-old cat is equivalent to about 15 human years. Cats develop very rapidly in their first year — reaching sexual maturity, full coordination, and near-adult size all within 12 months.
How old is a 5-year-old cat in human years?▾
A 5-year-old cat is approximately 36 human years old. After the first two years (which equal 24 human years), each additional cat year adds about 4 human years.
How old is a 10-year-old cat in human years?▾
A 10-year-old cat is approximately 56 human years old — firmly in the Senior life stage. At this age, regular vet check-ups become especially important.
My cat was born in 2020 — how old are they in human years?▾
A cat born in 2020 is around 5–6 years old (depending on the month), which equals roughly 36–40 human years. Enter your cat's exact age in years above to get a precise result.
Is the '1 cat year = 7 human years' rule accurate?▾
No — that's a myth. The actual formula is non-linear: year 1 = 15 human years, year 2 adds 9 more (24 total), and each year after that adds about 4 human years. This calculator uses the International Cat Care formula.
How is a cat year different from a dog year?▾
The aging rates are similar in structure but cats don't vary by size the way dogs do. Both species mature rapidly in the first two years, then slow to roughly 4 human years per animal year thereafter. Dogs age faster if they are large breeds.