Pets
Cat Age Calculator
Tell us how old your cat is and we'll convert that to human years using the standard veterinary scale — with senior-life-stage context to match.
0–11
Standard cat life stages
- Kitten · 0 – 1 yr
- Junior · 1 – 2 yr
- Adult · 3 – 6 yr
- Mature · 7 – 10 yr
- Senior · 11 – 14 yr
- Geriatric · 15+ yr
Adult
36 years
Cat age 5 years
Examples
1-year-old kitten
≈ 15 human years
5-year-old cat
≈ 36 human years
12-year-old cat
≈ 64 human years
How it works
Cats mature fast, then slow down. The standard veterinary conversion is piecewise:
year 1 = 15 · year 2 = +9 (24 total) · year 3+ = +4 per year
For ages under 1, we interpolate linearly within that first year.
Frequently asked questions
The widely accepted veterinary chart is: a cat's first year is roughly equivalent to 15 human years, the second year adds about 9 more (totaling 24), and each year after that adds about 4 human years.
Cats mature very quickly: by their second birthday they're roughly the equivalent of a 24-year-old human. The straight ×7 multiplier underestimates how fast cats grow up and overestimates aging in middle life.
Their birthdays count the same, but life expectancy differs sharply. Indoor cats commonly live 13–17 years; outdoor cats average significantly less due to predation, traffic, and disease.
Most veterinarians consider cats senior at around 11 (≈60 in human years) and geriatric at 15 (≈76). Schedule wellness visits twice a year once your cat hits 10.
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