Cat age chart

The full conversion at a glance, with the life stage veterinary guidelines use for each age.

Cat age	Human years	Life stage
6 months	8	Kitten
1 years	15	Adult
2 years	24	Adult
3 years	28	Adult
4 years	32	Adult
5 years	36	Adult
6 years	40	Adult
7 years	44	Mature
8 years	48	Mature
9 years	52	Mature
10 years	56	Mature
12 years	64	Senior
14 years	72	Senior
16 years	80	Senior
18 years	88	Senior
20 years	96	Senior

How the conversion works

The popular "multiply by 7" rule is wrong for cats. Cats mature extremely fast at first: by their first birthday a cat has reached the equivalent of mid-adolescence, and by their second they are a young adult of about 24. After that, aging slows to roughly four human years per cat year.

There is no scientifically exact formula — this is the convention used in veterinary practice, and the life-stage boundaries below follow the AAHA/AAFP feline life-stage guidelines. What matters for your cat's health is less the exact number and more the stage it puts them in.

What your cat's life stage means for care

Kitten (0–1 year · up to ~15 human years)

Growth is rapid: kittens need up to 2.5x the calories of an adult per kilogram, a full vaccination series, and monthly weight checks to confirm steady growth. This is also the easiest age to build habits like tooth-brushing and carrier training.

Adult (1–7 years · ~15–44 human years)

The long healthy middle. The main risks are slow ones: weight creep from free-feeding and dental disease. A monthly weigh-in and measured portions catch both years before they become visible.

Mature (7–11 years · ~44–60 human years)

Think of a person in their 50s: nothing is wrong, but screening starts to matter. Vets recommend twice-yearly checkups from here, and gradual weight loss in this stage is a symptom worth investigating, never a diet success.

Senior (11+ years · 60+ human years)

Kidney disease, hyperthyroidism, arthritis, and dental pain are common and very treatable when caught early. Watch water intake, appetite, weight, and jumping habits — small changes at this age carry real information.

See what to watch for at your cat's exact age and stage.

Get your cat's plan

This calculator is educational and uses the common veterinary conversion convention; it is not a medical assessment. Life-stage boundaries follow the AAHA/AAFP Feline Life Stage Guidelines.

Cat Age in Human Years: Calculator and Chart