Pet Age Calculator (Dog & Cat to Human Years)
How old is my pet in human years? Enter your dog or cat's age (years and months) to get a human-age estimate. Dogs age at different rates by size, so pick small, medium or large and the conversion adjusts (larger dogs age faster). It uses the common veterinary-chart approximation: about 15 human years for the first year, ~24 by age two, then a fixed amount each year after (small dog +4, medium +5, large +6, cat +4). It also shows the life stage — puppy/kitten, adult or senior. Everything runs locally; the age you enter is never stored or uploaded (only your species and size choice is saved on this device).
How to use
- Choose Dog or Cat (for a dog, also pick small, medium or large).
- Enter the pet's age in years and months.
- Read the human-equivalent age and the life-stage estimate.
FAQ
What formula is used?
About 15 human years for the first year, ~24 by age two, then a fixed amount per year after (small dog +4, medium +5, large +6, cat +4) — the approximation widely used on veterinary and pet-brand charts. Individual pets vary, so treat it as an estimate.
How do I pick the dog size?
By adult weight: small is roughly under 10 kg (22 lb), medium 10–25 kg, large above that. Larger dogs age faster, so the conversion changes with size.
I don't know my pet's exact age.
An approximate age in years and months is fine. Even for a rescue with an unknown birthday, entering the estimated age gives a human-age ballpark.
Is the age I enter stored?
No. All calculation runs in your browser; the age is never stored or uploaded. Only your species and size choice is saved on this device.