Aging in cats
The life expectancy of a cat is typically 15–17 years. However, some cats that are kept indoors may attain the age of 21 years or more.[1] By comparison, the average life expectancy of humans at birth is 67.2 years.[2] A one-year-old cat is roughly comparable, in developmental terms, to a 15-year-old-human. Subsequent years of a cat's life add progressively fewer years to its human age equivalent, so that a 15-year old cat is roughly comparable, developmentally, to a 76-year-old human.[3]
The table below shows the correspondence between a cat's chronological age and the age of a human at a comparable stage of development.
| Cat Years | Human Years |
|---|---|
| 1 | 15 |
| 2 | 24 |
| 3 | 28 |
| 4 | 32 |
| 5 | 36 |
| 6 | 40 |
| 7 | 44 |
| 8 | 48 |
| 9 | 52 |
| 10 | 56 |
| 11 | 60 |
| 12 | 64 |
| 13 | 68 |
| 14 | 72 |
| 15 | 76 |
| 16 | 80 |
| 17 | 84 |
| 18 | 88 |
| 19 | 92 |
| 20 | 96 |
| 21 | 100 |
The oldest cat ever recorded was Creme Puff, who died in 2005, having attained the age of 38 years, 3 days in cat years (168 in human years).