Why not just times seven?
Because cats grow up fast and then slow down. A cat is fully grown at one, and by two it’s a young adult, about 24 in human years. After that, each cat year adds about four human ones. The numbers here follow International Cat Care’s chart, which most vets use.
Cat years to human years
| 1 month | 1 |
|---|---|
| 3 months | 4 |
| 6 months | 10 |
| 1 year | 15 |
| 18 months | 21 |
| 2 years | 24 |
| 3 years | 28 |
| 5 years | 36 |
| 7 years | 44 |
| 10 years | 56 |
| 12 years | 64 |
| 15 years | 76 |
| 18 years | 88 |
| 20 years | 96 |
The six life stages
Kitten, up to 6 months. Junior, 7 months to 2 years. Adult, 3 to 6 years. Mature, 7 to 10. Senior, 11 to 14. Super senior, 15 and over. Vets’ own guidelines group them a little differently, and every cat ages at its own pace, so treat the stages as a guide, not a rule.
This is general information, not veterinary advice. Your vet can tell you how your cat is doing for its age.