Cat age chart
| Cat age | Human years | Life stage |
|---|---|---|
| 1 month | 1 | Kitten |
| 3 months | 4 | Kitten |
| 6 months | 10 | Kitten |
| 1 year | 15 | Young adult |
| 18 months | 21 | 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 | Mature adult |
| 11 years | 60 | Senior |
| 12 years | 64 | Senior |
| 13 years | 68 | Senior |
| 14 years | 72 | Senior |
| 15 years | 76 | Senior |
| 16 years | 80 | Senior |
| 17 years | 84 | Senior |
| 18 years | 88 | Senior |
| 19 years | 92 | Senior |
| 20 years | 96 | Senior |
| 21 years | 100 | Senior |
| 22 years | 104 | Senior |
| 23 years | 108 | Senior |
| 24 years | 112 | Senior |
| 25 years | 116 | Senior |
How cat years work
Cats grow up fast. A kitten goes from newborn to sexually mature in about six months, which is why the first year counts as roughly 15 human years. By the second birthday a cat is like a person in their mid-twenties. From then on, aging is steadier: each cat year equals about four human years.
human years = 24 + (cat age − 2) × 4, for cats aged 2 and older
Example: a 12-year-old cat is 24 + 10 × 4 = 64 in human years.
Unlike dogs, cats vary little in size, so one chart fits almost all breeds. Large breeds such as Maine Coons mature a little more slowly, but the human-year equivalents are close enough to use the same table.
Cat life stages
The American Animal Hospital Association (AAHA) and the American Association of Feline Practitioners (AAFP) define four life stages for cats:
- Kitten: birth to 1 year.
- Young adult: 1 to 6 years.
- Mature adult: 7 to 10 years.
- Senior: over 10 years.
Each stage has its own needs. Kittens need growth food and vaccinations. Mature adults tend to gain weight, so portion control matters. Seniors benefit from check-ups every six months, since kidney disease, hyperthyroidism, arthritis and dental disease are common and easier to manage when found early.
How long do cats live?
Indoor cats commonly live 12 to 18 years, and many reach their early 20s. Outdoor cats usually have shorter lives because of traffic, fights, parasites and infectious disease. Spaying or neutering, a healthy weight, dental care and regular vet visits all add years.
Frequently asked questions
How do you convert cat years to human years?
The first year of a cat's life equals about 15 human years, and the second year adds about 9 more, so a two-year-old cat is like a 24-year-old person. After that, each cat year counts as about 4 human years.
How old is a 10-year-old cat in human years?
A 10-year-old cat is about 56 in human years: 24 for the first two years plus 4 for each of the next eight.
When is a cat considered a senior?
The AAHA/AAFP feline life stage guidelines call cats over 10 years seniors. Cats from 7 to 10 are mature adults, from 1 to 6 young adults, and under 1 kittens.
How long do cats live?
Indoor cats commonly live 12 to 18 years, and many reach their early 20s. Outdoor cats tend to have shorter lives because of traffic, fights and disease.
Sources
- 2021 AAHA/AAFP Feline Life Stage Guidelines. Journal of Feline Medicine and Surgery, 2021.
- International Cat Care: cat age chart.
Human-year equivalents are approximations for general information, not veterinary advice. Last updated: October 2026.