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Pet Age Calculator — Free Online Calculator

Converts pet age (cat or dog) to the human age equivalent.

What is it?

The pet age calculator converts a dog's or cat's age in years to the equivalent in human years, using size-adjusted formulas rather than the oversimplified "×7" rule.

Formula

Dog (small breed, <10 kg): human years ≈ 12.5 × ln(dog age) × size factor Simplified table (medium dog): 1 yr=15, 2 yrs=24, then +4–5 per year after 2 Cat: 1 yr≈15, 2 yrs≈24, then +4 per year after 2

Example

A 7-year-old medium dog ≈ 44 human years (24 + 5×4). A 7-year-old cat ≈ 44 human years (24 + 5×4). A 7-year-old large dog ≈ 49–50 human years (large breeds age faster).

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