Cats age dramatically in their first two years — a 1-year-old cat is roughly equivalent to a 15-year-old human. After that, each cat year equals about 4 human years. This calculator follows the AAHA/AAFP Feline Life Stage Guidelines.
| Cat Age | Human Equivalent | Life Stage |
|---|---|---|
| 1 month | ~1 year | Kitten |
| 6 months | ~10 years | Kitten |
| 1 year | 15 years | Junior |
| 2 years | 24 years | Prime Adult |
| 5 years | 36 years | Prime Adult |
| 7 years | 44 years | Mature Adult |
| 10 years | 56 years | Senior |
| 12 years | 64 years | Senior |
| 15 years | 76 years | Geriatric |
| 20 years | 96 years | Geriatric |