Dog age calculator: dog years to human years
Enter your dog's age to see its human-year equivalent two ways. Neither method multiplies by seven, because dogs age fast in their first two years and more slowly after.
Work it out
- DNA formula (built on Labradors)
- 60
- Rule of thumb (medium dog)
- 44
Human-year equivalents, rounded. Both are estimates.
How the two numbers are worked out
- DNA formula. Human age = 16 × ln(dog age) + 31, from a 2020 study in Cell Systems that compared age-related DNA changes in dogs and people. It was built on Labrador retrievers, so it fits Labrador-sized dogs best.
- Rule of thumb. About 15 human years for a dog's first year, 9 for the second, and about 5 for each year after. It is written for a medium-sized dog.
The two disagree most for very young and very old dogs. Treat either number as a way to picture a life stage, not as a medical measurement. Larger breeds tend to be further along at the same age than small ones.
The sources, a worked table and the limits of each method are in How do dog years convert to human years? To find out when your dog counts as a senior, which depends on breed and size, read When is a dog considered a senior?
When to call your veterinarian
A calculator is not a reason for an urgent call. It is a good reason to ask one question at your next visit: "Based on breed and size, which life stage is my dog in, and how often should we be coming in?"
More good years.