Dog Age Calculator (Dog Years to Human Years)

The “multiply by seven” rule doesn’t hold up: dogs grow up much faster than that in their first two years, and big dogs age faster than small ones afterwards. This calculator gives you two modern estimates and tells you when your dog enters its senior years.

Two ways to convert dog years

• Size-based chart (used by the American Veterinary Medical Association): a dog’s first year equals about 15 human years, the second about 9, and each year after that 4–7 years depending on size.
• Epigenetic formula from a 2020 University of California San Diego study of Labrador retrievers: human age ≈ 16 × ln(dog age) + 31, based on changes in DNA methylation.

Dog years chart

FAQ

When is a dog a senior?

Roughly at 10 years for small dogs, 8 for medium, 7 for large and 6 for giant breeds. Twice-yearly vet checks are commonly recommended from then on.

What changes for senior dogs?

Joints stiffen and calorie needs usually drop. A supportive orthopedic bed and portion adjustments are two of the simplest changes that help.

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