petcalc

Questions from the bench

Is 1 dog year really 7 human years?

No. Dogs mature much faster than people at the start of life and more slowly later. The AKC chart, based on AVMA guidance, puts a 1-year-old dog at about 15 human years and a 2-year-old at about 24. After that, each year adds roughly 4 to 7 human years, depending on size.

When is a dog considered a senior?

The American Animal Hospital Association (AAHA) defines the senior stage as the last 25% of a dog's expected lifespan. Using US life expectancy by size, that is around 10.1 years for small dogs, 9.5 for medium, 8.6 for large and 7.1 for giant dogs.

Do small dogs live longer than large dogs?

On average, yes. In US veterinary records, small purebred dogs have a life expectancy of about 13.5 years at birth, compared with about 9.5 years for giant breeds. Research suggests large dogs die younger mainly because they age faster.

What is the most accurate dog age formula?

There is no single exact formula. The AKC chart accounts for size, which matters a lot. The UC San Diego formula (16 × ln(age) + 31) is based on DNA changes, but it was built from 104 Labrador Retrievers only.

How can I tell how old my rescue dog is?

Start with the shelter's estimate and ask your vet, who can narrow it down from teeth, eyes, coat and overall condition. Any estimate for an adult dog is a range, so use the Shelter range option to see the human-age range and life stage for both ends.