Pet Age in Human Years Calculator
Photo: Jacob Sierra / Pexels
Convert your pet's age into human years (modern formula).
The old "1 dog year = 7 human years" rule is wrong. Pets age much faster in their first two years and then slow down — and large dogs age faster than small ones. This calculator uses the modern AVMA formula (and the latest 2019 epigenetic dog-ageing research) to give a far more accurate human-equivalent age.
How this calculator works
For dogs, the calculator uses the AVMA approximation: year 1 ≈ 15 human years, year 2 ≈ 9 more (so age 2 ≈ 24), then 4–6 more per year depending on size. For cats: year 1 ≈ 15, year 2 ≈ 9 more (age 2 ≈ 24), then 4 per year.
Frequently asked questions
Why was the "× 7" rule wrong?
It assumed linear ageing, but dogs and cats grow up much faster than humans in the first 2 years and slow down afterwards. A 1-year-old dog is roughly equivalent to a 15-year-old human, not 7.
Are large dogs really older for their age?
Yes. A 7-year-old Great Dane is biologically closer to a 60-year-old human, while a 7-year-old Chihuahua is more like 44.
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