Dog and Cat Age Calculator

Estimate your pet’s age in human years. Dogs age fastest in their first two years; large breeds age faster after that.

What Do You Want to Find?
Decimals work: 1.5 years is 18 months.
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Human years
Rule used
Life stage
DNA-methylation estimate (dogs)
Work

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How Pet Age Is Estimated

The old "multiply by 7" rule is too simple. Veterinary groups use a fast first two years, then a steadier rate:

Dogs (AVMA): year 1 ≈ 15, year 2 ≈ +9, then about +5 per year
Cats (AAHA/AAFP): year 1 ≈ 15, year 2 ≈ +9 (24), then +4 per year

Larger dogs age faster after about age 2, so this page uses +4 per year for small dogs up to +7 for giant breeds, a common size adjustment. The DNA-methylation formula from a 2020 study of Labrador retrievers is shown for comparison.

Worked Example

Tips

These are rough guides; breed, health and lifestyle matter more than any formula. Ask your vet when to start senior checkups.