Find out how old your cat is in human years — using the AAFP/AAHA Feline Life Stage formula.
Editorially ReviewedYour cat's life stage helps you understand what to expect — from kitten energy to senior care.
Life-stage care guides, new calculators, and seasonal reminders — one email a week.
The formula used by feline veterinarians.
From kitten to geriatric, what to expect at each stage.
Signs that need veterinary attention.
More calculators for cat owners.
Cats age fast in their first two years, then slow down significantly. The AAFP (American Association of Feline Practitioners) and AAHA use a three-phase model that produces a much more accurate result than the popular "×7" myth.
Here's a quick reference for converting your cat's age to human years and identifying their life stage:
| Cat Age | Human Age | Life Stage |
|---|---|---|
| 6 months | 10 | Kitten |
| 1 year | 15 | Junior |
| 2 years | 24 | Junior |
| 3 years | 28 | Adult |
| 5 years | 36 | Adult |
| 7 years | 44 | Mature |
| 10 years | 56 | Senior |
| 13 years | 68 | Senior |
| 15 years | 76 | Geriatric |
| 18 years | 88 | Geriatric |
| 20 years | 96 | Geriatric |
Understanding your cat's life stage helps you anticipate what they need: an active 3-year-old needs play and enrichment, while a 13-year-old benefits from softer food, joint support, and more frequent monitoring. Indoor cats often live to 15+, so even a "middle-aged" cat may have a decade of life ahead.
Cats age fast in their first two years, then slow down. A 1-year-old cat is approximately 15 in human years. A 2-year-old cat is approximately 24.
After year 2, add 4 human years per cat year — so a 5-year-old cat is 36, a 10-year-old cat is 56, and a 15-year-old cat is 76 in human years.
Indoor cats typically live 13-17 years on average, with many living into their 20s.
Outdoor cats have significantly shorter lifespans, averaging 2-5 years due to risks from cars, predators, disease, and toxins. The oldest documented cat lived to 38.
Following AAFP/AAHA feline life stage guidelines, cats are considered mature at 7-10 years, senior at 11-14 years, and geriatric at 15+ years.
Senior cats benefit from twice-yearly vet visits and screening for common age-related conditions like kidney disease, hyperthyroidism, and arthritis.
Yes — significantly. Indoor cats typically live 13-17 years, while outdoor cats average only 2-5 years.
The main causes of early death for outdoor cats are vehicle injuries, attacks from other animals, infectious diseases like FIV and FeLV, and accidental poisoning. Enriched indoor environments with climbing, hunting toys, and window perches give cats stimulation without the risk.
Common signs of aging in cats include: decreased activity and longer sleep periods, weight loss or weight gain, decreased grooming (matted or unkempt fur), increased vocalization (especially at night), changes in litter box habits, decreased jumping or climbing, cloudy eyes, and changes in appetite or thirst.
Some changes are normal, but sudden or dramatic changes should always be checked by your vet.