How Old Is Your Furry Friend in Human Years?

Our calculator uses the 2020 UC San Diego scientific formula based on DNA methylation research, combined with breed-specific and size-based adjustments. While no formula is perfect for every individual dog, this method is considered the most scientifically accurate approach currently available.

No, the 7:1 ratio is an outdated myth from the 1950s. Dogs actually age much faster in their first few years, then slow down. A 1-year-old dog is roughly equivalent to a 30-year-old human, not 7. Our calculator uses the scientific logarithmic formula that accounts for this non-linear aging pattern.

Larger dogs generally have shorter lifespans and age faster than smaller dogs. Scientists believe this is related to faster cell growth and higher metabolic rates in large breeds. A Great Dane might be considered senior at 6-7 years, while a Chihuahua may not reach senior status until 11-12 years. Our calculator adjusts for these size-based differences.

If you know your dog's breed, select it for the most accurate calculation as we have breed-specific data. If your dog is a mixed breed or you're unsure, use the size category based on your dog's adult weight: Small (under 20 lbs), Medium (20-50 lbs), Large (50-100 lbs), or Giant (over 100 lbs).

For mixed breeds, estimate your dog's adult weight and select the corresponding size category (Small, Medium, Large, or Giant). The calculator will use size-based aging factors which work well for mixed breed dogs. If you know the dominant breed in your mix, you can also try selecting that breed.

Yes! The formula works for dogs of all ages, including puppies. In fact, puppies show the most dramatic age conversion - a 1-year-old dog is already equivalent to about 30 human years due to their rapid early development.