🐱 Cat Age Calculator
Convert your cat's age into human-equivalent years — cats age very fast in their first two years, then more gradually after that.
15 years for year 1, +9 for year 2, +4/year after.
How the Cat Age Calculator works
The commonly published formula treats year one as roughly 15 human years, year two adds about 9 more, and each year after that adds about 4 human years.
Step-by-step calculation
- 1Enter your cat's age.
- 2Year 1 = 15, year 2 adds 9, each later year adds 4.
Worked example
A 6-year-old cat: 15 + 9 + 4 × 4 = 40 human years.
Cat Age Calculator examples
| Cat's age (years) | Human-equivalent age |
|---|---|
| 1 | 15 human years |
| 2 | 24 human years |
| 4 | 32 human years |
| 7 | 44 human years |
| 10 | 56 human years |
| 15 | 76 human years |
Other inputs kept at the calculator's default values. Results calculated by this calculator.
Why use a Cat Age Calculator?
Know your cat's life stage for health and feeding.
Important factors that can affect your results
- Indoor vs outdoor cats.
- Breed.
- Health.
Frequently asked questions
Why do the first two years count for so much?
Cats reach physical and reproductive maturity very quickly compared to humans, which is reflected in the steep early-age formula.
Is indoor vs outdoor lifestyle factored in?
No — this uses a general age-based formula only.
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Last reviewed November 2026 · How we build and check our tools · Report a problem