Pet age calculator
Estimate your dog or cat's age in human years.
Roughly in human years
40
A fun estimate. Runs entirely in your browser.
How to use this tool
- Choose dog or cat. For dogs, pick the size, since larger dogs age faster.
- Enter your pet's age in years.
- Click Calculate for the human-years estimate.
How the estimate works
Pets age quickly in their first two years, then more steadily. This tool counts the first year as about 15 human years, the second as about 9 more, and each year after that at a per-year rate that depends on the species and a dog's size.
A real example
A five year old medium dog lands around the early forties in human terms, which lines up with the middle-age care many vets recommend at that stage, like more attention to joints and weight.
Common questions
Why does size matter for dogs?
Large breeds tend to have shorter lifespans and age faster in later years, so the per-year rate is higher than for small breeds.