Dog Age Calculator
Convert your dog’s age into human-equivalent years — sized for your breed.
Size by adult weight: Small under 10 kg · Medium 10–25 kg · Large 25–45 kg · Giant over 45 kg.
How old is your dog in human years?
Enter your dog’s age and pick its size class to see roughly how old it is in human-equivalent years. The popular “multiply by seven” rule is misleading: dogs mature very quickly in their first two years, then age more steadily. This calculator uses the widely cited size-based chart, where a dog reaches about 15 human years by its first birthday and about 24 by its second, after which each additional year adds a few more human years depending on body size.
Why size matters
Small dogs tend to live longer and age more slowly, while large and giant breeds age faster and reach their senior years sooner. That is why a 7-year-old small dog and a 7-year-old giant dog are not at the same life stage. Choosing the right size band gives a more realistic estimate than a single one-size-fits-all formula.
FAQ
Is one dog year really seven human years? No. That old rule of thumb overstates the early years and understates later ones. A dog’s first year alone is closer to 15 human years.
How do I know my dog’s size class? Use adult weight: roughly under 10 kg is small, 10–25 kg medium, 25–45 kg large, and over 45 kg giant. Breed charts can help if you are unsure.
Is this an exact medical figure? No. It is a popular estimate for fun and rough comparison, not a veterinary measurement. Real aging varies by breed, genetics, and health, so ask your vet for guidance specific to your dog.