Convert your dog's age into human years, adjusted for size. Enter your details below and get an instant, easy-to-read result.
Dog Age Calculator
Convert your dog's age into human years, adjusted for size.
Dog Age Calculator
How this calculator works
Dogs do not age at one steady rate. The first year goes by fast — a one-year-old dog is already comparable to a 15-year-old person — and the second year adds about nine more. After that, size takes over: smaller dogs tend to age more slowly than large and giant breeds. This calculator uses that 15/24 method and then adds 4 to 7 human years per dog year depending on the size group you choose.
Frequently Asked Questions
Is the old "one dog year equals seven human years" rule accurate?
Not really. That rule ignores how quickly dogs mature in their first two years and how much size matters later on, which is why this calculator uses the more accurate 15/24 method with size-based aging after age two.
Why does my dog's size change the result?
Veterinary research shows larger breeds tend to age faster once they reach adulthood, so the calculator adds more human years per dog year for large and giant dogs than for small ones.
What can I do to keep my dog younger for longer?
A healthy weight, daily exercise, routine veterinary checkups and a balanced diet are the factors most strongly linked to a longer, healthier life in dogs.