Cat Age Calculator
Convert cat years to human years: about 15 at one year, 24 at two years, then roughly four human years per calendar year.
How to use this cat age calculator
Cat age calculators drop the ×7 myth too. Cats mature quickly (often called a “teen” by one year and a young adult by two), then age about four human years per calendar year. Indoor cats frequently outlive outdoor cats; the chart does not know that.
Use months for kittens. Senior care (kidneys, teeth, weight) starts well before the chart says “old.” This is not a substitute for a wellness exam.
Formula
Worked example
A 4-year-old cat is about 24 + 2 × 4 = 32 human years. A 10-year-old is about 56.
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Frequently asked questions
How old is my cat in human years?
About 15 at 1 year, 24 at 2 years, then add 4 human years for each year after that.
Is a 1-year-old cat 7 in human years?
No — closer to 15. Cats mature faster than the old ×7 rule.
When is a cat a senior?
Often 10–12 calendar years, sometimes earlier for big or ill cats. Ask your vet.
Indoor vs outdoor?
Lifestyle changes lifespan more than this formula. The math is the same; the outcome is not.
Kitten months?
Enter 0 years and the months (for example 6 months ≈ 7.5 human years on the first-year 15× scale).
Results are estimates for informational purposes and are not financial, legal, or professional advice. Last reviewed 2026-08-20.