Dog Age Calculator
The old seven-to-one rule for dog years is misleading. Dogs age quickly in their first two years, then more slowly. This page uses a stepped estimate instead, and the pace after year two depends on size.
- Free
- Works offline after your first visit
- Saves on this device
- No sign-up
- Updated
How it works
The first year counts as 15 human years and the second as 9 more. After that, each dog year adds a number of human years that depends on size: 4 for small, 5 for medium and 6 for large dogs in this estimate.
Pick the size class that matches your adult dog. A mixed or unusual build may fall between two choices.
Worked example
A dog that is 5 years old, in the size class you chose, is about 39 in human years.
Questions
Is the seven-to-one rule wrong?
It is a rough average over a whole life. Dogs age fast at first, so the first two years count for much more than seven each.
Does this measure my dog's health?
No. It only converts age into a human-years comparison. It does not judge how healthy a dog is.
Why does size change the answer?
Smaller dogs often live longer than large ones, so their human-years figure climbs more slowly after year two.
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