How Cat Years Work
A 1-year-old cat ≈ 15 human years, year 2 adds 9, then 4 human years per cat year. A 10-year-old cat is ~56 human years. Cats age approximately 15 human years in their first year, 9 in their second year, and then 4 human years per cat year after that. A 3-year-old cat is ~28 human years; a 10-year-old cat is ~56; a 15-year-old cat is ~76. Unlike dogs, cat aging is relatively consistent across breeds (Siamese may live slightly longer).
Source: AAFP Feline Life Stage GuidelinesCat Life Stages Defined by AAFP
AAFP defines 6 feline life stages: Kitten (0-6mo), Junior (7mo-2yr), Prime (3-6yr), Mature (7-10yr), Senior (11-14yr), Geriatric (15+yr). The American Association of Feline Practitioners (AAFP) defines six life stages: Kitten (0-6 months), Junior (7 months-2 years), Prime (3-6 years), Mature (7-10 years), Senior (11-14 years), and Geriatric (15+ years). Each stage comes with different nutritional, preventive care, and health screening recommendations.
Source: AAFP Feline Life Stage Guidelines (2021)How Long Do Cats Live?
Indoor cats live 12-18 years on average (some reach 20+); outdoor cats average 2-5 years due to traffic, predators, and disease. Indoor cats live 12-18 years on average; some reach 20+. Outdoor cats average 2-5 years due to traffic, predators, and disease. Well-cared-for indoor cats in their late teens are common. The oldest recorded cat (Creme Puff, Texas) lived 38 years. Genetics, diet, preventive care, and indoor lifestyle are the strongest longevity predictors.
Source: ISFM Feline Care GuidelinesSenior Cat Health Screening
AAFP recommends annual blood work from age 7-8, biannual exams at 11+, and more frequent monitoring at 15+ for cats. AAFP recommends: annual blood work starting at age 7-8 (Mature stage), biannual exams at 11+ (Senior), and more frequent monitoring at 15+ (Geriatric). Key screens include: CBC, biochemistry panel, urinalysis, T4 (thyroid), and blood pressure. Cats hide illness — regular screening catches kidney disease, hyperthyroidism, and diabetes early.
Source: AAFP Senior Care GuidelinesData verified by petsMetrics using peer-reviewed veterinary sources. Citations: ASPCA, AVMA, AAFP. Last reviewed: 2026.