How old is your pet in human years?
Pick dog or cat, enter an age or birthday, and get the answer vets use, with the DNA formula and the old ×7 rule alongside for comparison.
Enter an age to see human years.
The default is the size-based vet chart. See how pet age is calculated.
Dog years to human years
| Dog age | Small | Medium | Large | Giant |
|---|---|---|---|---|
| 1 year | 15 | 15 | 15 | 12 |
| 2 years | 24 | 24 | 24 | 22 |
| 3 years | 28 | 28 | 28 | 31 |
| 4 years | 32 | 32 | 32 | 38 |
| 5 years | 36 | 36 | 36 | 45 |
| 6 years | 40 | 42 | 45 | 49 |
| 7 years | 44 | 47 | 50 | 56 |
| 8 years | 48 | 51 | 55 | 64 |
| 9 years | 52 | 56 | 61 | 71 |
| 10 years | 56 | 60 | 66 | 79 |
The default is the size-based vet chart. See how pet age is calculated.
Cat years to human years
| Cat age | Human years | Life stage |
|---|---|---|
| 1 year | 15 | Young adult |
| 2 years | 24 | Young adult |
| 3 years | 28 | Young adult |
| 4 years | 32 | Young adult |
| 5 years | 36 | Young adult |
| 6 years | 40 | Young adult |
| 7 years | 44 | Mature adult |
| 8 years | 48 | Mature adult |
| 9 years | 52 | Mature adult |
| 10 years | 56 | Senior |
The default is the size-based vet chart. See how pet age is calculated.
FAQ
What is the difference between dog years and cat years?
Both grow up fast: a one-year-old cat or medium dog is about 15 in human years, and about 24 at two. After that, cats add about four human years per year, while dogs add four to nine depending on size, so by middle age a large dog is "older" than a cat of the same age.
Which pet age method should I use?
The size-based vet chart, which is the default here. The DNA formula is interesting but was measured only in Labrador Retrievers, and the ×7 rule is a myth. You can switch between all three in the calculator.
Can I work out my pet's age from its birthday?
Yes. Choose "I know the birthday" and pick the date. The calculator counts the full months since then.
How do I share my pet's age in human years?
Add your pet's name and copy the share link. Anyone who opens it sees your pet's age in human years and can work out their own pet's.