Cat years calculator: your cat's age in human years
Use our free cat years calculator to convert your cat's age into human years, or a human age into cat years. Cats age fast at first: a 1-year-old cat is like a 15-year-old person, a 2-year-old like a 24-year-old, and after that each cat year equals about 4 human years.
Enter your cat's age
Uses the International Cat Care / AAFP method: the first year equals 15 human years, the second adds 9, and every year after adds about 4.
Your cat is roughly
36 human years
Prime adultQuick answer
- 1 cat year = 15 human years; 2 cat years = 24.
- After age 2, add about 4 human years for every cat year.
- A cat is a senior from 11 and a super senior from 15.
- Kittens become adult cats at about 12 months, but many breeds keep filling out until 2 to 4.
Cat years chart: 1 to 25 years
This cat age chart uses the method followed by International Cat Care and the American Association of Feline Practitioners (AAFP). Find your cat's age on the left to see the human equivalent and its life stage.
| Cat's age | Human years | Life stage |
|---|---|---|
| 1 month | 1 | Kitten |
| 3 months | 4 | Kitten |
| 6 months | 10 | Kitten |
| 1 year | 15 | Junior |
| 2 years | 24 | Junior |
| 3 years | 28 | Prime adult |
| 4 years | 32 | Prime adult |
| 5 years | 36 | Prime adult |
| 6 years | 40 | Prime adult |
| 7 years | 44 | Mature |
| 8 years | 48 | Mature |
| 9 years | 52 | Mature |
| 10 years | 56 | Mature |
| 11 years | 60 | Senior |
| 12 years | 64 | Senior |
| 13 years | 68 | Senior |
| 14 years | 72 | Senior |
| 15 years | 76 | Super senior |
| 16 years | 80 | Super senior |
| 17 years | 84 | Super senior |
| 18 years | 88 | Super senior |
| 19 years | 92 | Super senior |
| 20 years | 96 | Super senior |
| 21 years | 100 | Super senior |
| 22 years | 104 | Super senior |
| 23 years | 108 | Super senior |
| 24 years | 112 | Super senior |
| 25 years | 116 | Super senior |
How cat years are calculated
- First year = 15 human years. By their first birthday, kittens have gone through infancy, childhood and puberty, roughly like a mid-teen.
- Second year = 9 more human years (24 in total). By 2, a cat is a fully mature young adult.
- Each year after = about 4 human years. So a 5-year-old cat is 24 + (3 × 4) = 36.
The quick formula for cats over 2 is: human years = 24 + 4 × (cat's age − 2). The figures are a guide: genetics, size, breed, diet and whether a cat lives indoors all affect how quickly it ages.
Popular ages in cat years
2 years in cat years
A 2-year-old cat is about 24 in human years: a young adult, fully grown in most breeds.
4 years in cat years
A 4-year-old cat is about 32: in its prime, usually healthy and energetic.
7 years in cat years
A 7-year-old cat is about 44: entering the mature stage, when some vets suggest senior food.
9 years in cat years
A 9-year-old cat is about 52: a good time to start yearly blood tests.
10 in cat years
A 10-year-old cat is about 56: the last year of the mature stage.
11 years in cat years
An 11-year-old cat is about 60: officially a senior cat.
13 in cat years
A 13-year-old cat is about 68: a senior who benefits from 6-monthly check-ups.
14 years in cat years
A 14-year-old cat is about 72: watch closely for weight loss, thirst and stiffness.
17 years in cat years
A 17-year-old cat is about 84: a super senior needing gentle routines.
18 in cat years
An 18-year-old cat is about 88. Many well-cared-for cats reach this age.
19 years in cat years
A 19-year-old cat is about 92: a remarkable age needing extra comfort.
20 in cat years
A 20-year-old cat is about 96: very elderly, close to a human centenarian.
Cat life stages explained
| Life stage | Cat's age | Human equivalent | What to focus on |
|---|---|---|---|
| Kitten | 0–6 months | 0–10 | Vaccinations, worming, socialisation, neutering |
| Junior | 7 months–2 years | 12–24 | Play, training, weight checks after neutering |
| Prime adult | 3–6 years | 28–40 | Yearly check-ups, dental care, healthy weight |
| Mature | 7–10 years | 44–56 | Yearly blood tests, watch weight and teeth |
| Senior | 11–14 years | 60–72 | 6-monthly checks, blood pressure, kidney and thyroid tests |
| Super senior | 15+ years | 76+ | Comfort, arthritis care, easy-access litter trays and beds |
When does a kitten become a cat?
Most kittens are considered adult cats at about 12 months. They can become sexually mature from as young as 4 months, which is why early neutering matters; see our guide to a cat in heat. Physical growth continues longer in some breeds: Maine Coons can keep growing until 3 to 5 years, and British Shorthairs fill out until about 3. Kittens can usually switch from kitten food to adult food at around 12 months.
How to tell how old a cat is
If you've adopted a rescue or found a stray, a vet can estimate age from:
- Teeth: kittens get adult teeth at 4 to 6 months; tartar and wear increase with age.
- Eyes: older cats may have cloudier lenses and a lacy iris.
- Coat: grey hairs and a coarser coat appear in older cats.
- Body shape: seniors often lose muscle along the spine and hips.
- Activity: younger cats tend to be more playful and agile.
If you've found a cat and aren't sure whether it's owned, see how to know if a cat is a stray.
Caring for a cat at every age
Young cats in cat years: 0 to 2
Book kitten vaccinations, start a flea and worming routine and arrange neutering. See cat vaccination costs, neutering costs and our flea treatment guide.
Adult cats: 3 to 10
Keep your cat at a healthy weight with measured meals. Check body condition with our cat weight checker and set portions with the cat food calculator.
Senior cats: 11 and over
Older cats are prone to kidney disease, an overactive thyroid, arthritis, high blood pressure and dental disease. Watch for drinking more, weight loss, vomiting and changes in behaviour, and see our guides to renal diets for cats, Thyronorm for overactive thyroid, Metacam for arthritis, the cat dental chart and cat blood pressure.
Older cats often hide pain and illness. Small changes, such as sleeping more, missing the litter tray or eating less, can be early signs of a problem. Book a vet check if anything changes.
How long do cats live?
Most UK cats live around 12 to 18 years, and indoor cats often live longer than cats that roam near busy roads. Mixed-breed cats tend to live slightly longer than some pedigrees. Neutering, vaccinations, a healthy weight, dental care and regular vet checks all help your cat live a long life. Pet cat insurance can make senior care more affordable, but it's best to take out a policy while your cat is young.
FAQs
How old is 13 in cat years?
A 13-year-old cat is about 68 in human years. That makes it a senior cat, and vets recommend check-ups every 6 months, including blood pressure and blood tests.
How old is 10 in cat years?
A 10-year-old cat is roughly 56 in human years, at the end of the 'mature' life stage. From around this age, vets often suggest yearly blood tests.
How old is 18 in cat years?
An 18-year-old cat is about 88 in human years: a super senior. Many cats now reach their late teens with good care and regular vet checks.
How old is a 2-year-old cat in human years?
A 2-year-old cat is about 24 in human years. Cats age quickly in their first two years, then slow to about 4 human years per cat year.
When does a kitten become a cat?
Kittens are generally considered adult cats at around 12 months old, when they reach sexual and most of their physical maturity. Large breeds such as Maine Coons and slow-maturing breeds like British Shorthairs keep growing until 2 to 4 years.
Is one cat year equal to 7 human years?
No. The '7 years' rule is a myth and isn't even accurate for dogs. Cats mature much faster early on: one cat year equals about 15 human years, then the rate slows to roughly 4 human years per cat year after age 2.
How old is the oldest cat?
The oldest cat on record, Creme Puff from Texas, lived to 38 years old, which is over 160 in human years. Most indoor cats today live to around 12 to 18.
Sources and further reading
This guide is for general information only and is not a substitute for advice from a vet. Medicines, doses and costs change: always follow your vet and the product leaflet. If your cat is unwell or you think it has eaten something toxic, contact your vet or an emergency vet straight away.
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