Multiply your dog’s age by 7 to get their human age. It’s simple, memorable — and completely wrong.

How Dogs Actually Age

A dog experiences roughly 15 human years in their first year of life. Year two adds approximately 9 more. After that, ageing slows — and the rate depends almost entirely on breed size. Small breeds age at ~4 human years per year after age 2. Giant breeds age at ~7 human years per year.

Why Breed Size Changes Everything

Larger dogs age faster. A 10-year-old Chihuahua is a healthy senior. A 10-year-old Great Dane is elderly. This is why giant breeds have shorter average lifespans despite their size.

Calculate Your Dog’s Real Age

Use our Dog Age to Human Years Calculator to find your dog’s accurate human equivalent instantly. Just enter their age and breed size.