How to tell your cat's age: a vet-backed guide
Published on 2026-04-14
Cats do not come with birth certificates. If you adopted a stray or rescued an adult cat, here are the signs vets use to estimate age — from teeth to coat to eyes.
Teeth: the most reliable clue
Veterinarians rely heavily on teeth to estimate cat age. Kittens have small, white deciduous teeth until 4 months, then adult teeth erupt. Little tartar and clean whites suggest under 2 years; noticeable yellowing 3–5; significant tartar and possibly missing teeth 5–10; worn teeth with gum recession usually 10+. Dental health also depends on diet, so use this as a rough guide.
Coat and body condition
Young cats have soft, fine coats with bright colors. Middle-aged cats develop thicker, slightly coarser fur. Senior cats often show grey hairs around the muzzle, a less glossy coat, and sometimes patches of thinning. Muscle tone also changes: kittens and young adults are lean and springy, while older cats often carry slightly more fat and lose muscle around the spine.
Eyes and behavior
A young cat's iris is smooth and clear. By age 10+, many cats develop a cloudy haze (lenticular sclerosis) that is normal aging. Behavior also tells a story: kittens play constantly; adults alternate play and rest; seniors sleep more and may seek warmth and quiet spots. Combine all three signs for the most accurate estimate.