At what age is a cat considered a senior?

The 2021 AAHA/AAFP Feline Life Stage Guidelines define senior cats as over 10 years old. Cats aged 7 to 10 are mature adults, roughly equivalent to middle age in people.

Cat Age Calculator Cat Years to Human Years & Life Stage

Convert your cat’s age to human years, find its veterinary life stage and see what care it needs right now. Works from a birth date or an age in years. You can also estimate the age of a rescue or stray cat from the signs you see.

AAHA/AAFP Feline Life Stage Guidelines RVC VetCompass lifespan study (2024)

By Manzoor Ahmad · Updated October 18, 2026

Enter a birth date, or the age in years and months.

Cat’s name (optional)

Date of birth (or adoption estimate)

or enter age

Years

Months

Sex

Lifestyle

—Cat years

—Human years

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Where your cat is on the feline life timeline

avg ~11.7 yrs

05101520 yrs

Next birthday——

Senior in—at 10+ years

Vet checkups—AAHA/AAFP

Ages per year—human years now

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Care checklist for this life stage

How do you convert cat years to human years?

A cat’s first year equals about 15 human years, and its second year adds about 9 more, so a 2-year-old cat is roughly 24. After that, each cat year equals about 4 human years. A 5-year-old cat is about 36 in human years, a 10-year-old about 56, a 15-year-old about 76 and a 20-year-old about 96. The old “multiply by 7” rule underestimates young cats and overestimates old ones.

Key facts at a glance

Life stages (AAHA/AAFP 2021): kitten 0–1 year, young adult 1–6, mature adult 7–10, senior over 10.
Cats should see a vet at least once a year, and seniors at least every 6 months.
A 2024 UK study of 7,936 cats found an average life expectancy of 11.74 years. Females lived about 16 months longer than males.
The longest-lived breed in that study was the Burmese (14.42 years) and the shortest the Sphynx (6.68 years).
Overweight cats tended to live shorter lives, so healthy weight is one of the biggest factors you can control.

Cat age chart: cat years to human years

Look up your cat’s age below. For an exact figure, including months or a birth date, use the calculator above.

Cat age	Human equivalent	Life stage
1 month	2 years	Kitten
2 months	3 years	Kitten
3 months	5 years	Kitten
4 months	7 years	Kitten
6 months	10 years	Kitten
9 months	12 years	Kitten
1 year	15 years	Young adult
1.5 years	20 years	Young adult
2 years	24 years	Young adult
3 years	28 years	Young adult
4 years	32 years	Young adult
5 years	36 years	Young adult
6 years	40 years	Young adult
7 years	44 years	Mature adult
8 years	48 years	Mature adult
9 years	52 years	Mature adult
10 years	56 years	Mature adult
11 years	60 years	Senior
12 years	64 years	Senior
13 years	68 years	Senior
14 years	72 years	Senior
15 years	76 years	Senior
16 years	80 years	Senior
17 years	84 years	Senior
18 years	88 years	Senior
19 years	92 years	Senior
20 years	96 years	Senior
21 years	100 years	Senior
22 years	104 years	Senior
23 years	108 years	Senior
24 years	112 years	Senior
25 years	116 years	Senior

The four feline life stages

Vets group cats into life stages because each comes with different health risks and care priorities. These are the stages defined in the 2021 AAHA/AAFP Feline Life Stage Guidelines:

Kitten

Birth – 1 year · ≈ 0–15 human years

Rapid growth, vaccinations, deworming and socialization. Cats can reach puberty from about 4–6 months, so plan spaying before then. The cat pregnancy calculator helps if an accidental mating has already happened.

Young adult

1 – 6 years · ≈ 15–40 human years

Peak health. The focus is on keeping a lean weight, dental care, play and yearly checkups. Many cats gain weight after neutering.

Mature adult

7 – 10 years · ≈ 44–56 human years

Equivalent to middle age. Early signs of dental disease, arthritis and weight change appear, and baseline bloodwork becomes valuable.

Senior

Over 10 years · ≈ 60+ human years

Kidney disease, hyperthyroidism, arthritis and dental problems become common. Checkups move to every 6 months.

How the cat age calculator works

Cats mature very quickly. By their first birthday they’re physically comparable to a mid-teen human, and by two they’re like a young adult in their mid-twenties. Aging then slows to a steady pace of roughly four human years per cat year. The calculator follows this widely used veterinary pattern and smooths the kitten months so a 6-month-old reads about 10 human years.

Age 0–1 year: 0 → 15 human years (about 10 by 6 months)

Age 1–2 years: 15 → 24 human years

Age 2+ years: human age = 24 + 4 × (cat age − 2)

Estimating the age of a rescue or stray cat

The “Unknown age” tab uses the same clues vets look for: teeth, eyes, coat and muscle. Baby teeth appear in the first weeks, adult teeth replace them by about 6 months, and tartar and wear build up over the years. Lens cloudiness and graying suggest a senior cat. It’s an estimate only. Your vet can narrow it with a full exam.

Worked example: Milo, 5 years old

Human age: 24 + 4 × (5 − 2) = 36 human years.
Life stage: young adult (1–6 years), with mature adulthood starting at 7.
Senior in: about 5 years, at age 10.
Care focus: yearly checkup, lean weight and dental care. Each extra cat year now adds about 4 human years.

These are the calculator’s default values.

How long do cats live?

A large 2024 study by the Royal Veterinary College’s VetCompass program analyzed 7,936 cats in UK veterinary practices and found an average life expectancy of 11.74 years. Many cats live well into their late teens, and some past 20.

Sex

Female cats lived about 16 months longer than males on average.

Breed

Burmese cats had the longest life expectancy (14.42 years) and the Sphynx the shortest (6.68 years).

Body weight

Overweight cats tended to have shorter lives, so keeping your cat lean is one of the most powerful things you can do.

Lifestyle matters too. Indoor cats avoid traffic, fights and many infections, and are widely reported to live longer than cats that roam outdoors. To keep your cat at a healthy weight at every age, check its daily energy needs with the cat calorie calculator.

Signs your cat is getting older

Behavior

More sleep, less jumping, avoiding high perches, vocalizing at night or seeming confused. These can be signs of arthritis or cognitive changes.

Body

Weight loss or gain, a bonier spine, a less groomed or matted coat, cloudy eyes and gray hairs around the face.

Thirst and litter box

Drinking more and producing larger clumps can point to kidney disease, diabetes or hyperthyroidism. Report it to your vet promptly.

A pharmacist’s notes on medicines for older cats

Never give acetaminophen (Tylenol) or human pain relievers. Cats can’t safely break them down, and even small amounts can be fatal at any age.
Arthritis pain is common and treatable, but only with vet-prescribed, cat-specific options. Kidney function needs checking first.
Senior cats often take several medicines. Keep an updated list, and ask your vet or pharmacist about pill pockets, compounded liquids or transdermal gels if pilling is a struggle.
Dog flea products containing permethrin can kill cats. Use only products labeled for cats.
Cats are highly sensitive to onion and garlic. Even seasoned leftovers can cause anemia, as the onion and garlic toxicity calculator explains.

Related cat and dog calculators

Use your cat’s life stage to plan the next steps:

Nutrition by ageDaily calories for your catEnergy needs change from kitten to senior. Find the right daily calories for your cat’s age, weight and activity. PortionsHow much to feed your catTurn calories into grams of dry food or cans of wet food per day for any life stage. Kittens on the wayCat pregnancy due dateYoung queens can get pregnant from about 4 months. Estimate a due date and week-by-week milestones. Multi-pet homesDog years to human yearsDogs age differently from cats, and size matters. Compare your dog’s age in human years. SafetyOnion & garlic toxicity checkCats are the most sensitive species to onion and garlic. Check any exposure from leftovers or seasonings. All toolsPets Calculators hubEvery dexocalc calculator for cat and dog owners, from age and nutrition to pregnancy and safety.

Cat age calculator FAQs

The first cat year equals about 15 human years, the second adds about 9 (24 total), and each year after adds about 4. So a 3-year-old cat is about 28, a 7-year-old about 44 and a 12-year-old about 64 in human years.

No. That rule doesn’t fit cats. Cats age very quickly in the first two years (reaching about 24 in human terms) and then about 4 human years per cat year.

The 2021 AAHA/AAFP Feline Life Stage Guidelines define senior cats as over 10 years old. Cats aged 7–10 are mature adults, roughly equivalent to middle age in people.

About 15 human years, similar to a mid-teenager. Most cats are close to full adult size by their first birthday.

About 56 human years. A 10-year-old cat is at the end of the mature adult stage and moving into its senior years.

About 76 human years. Senior cats this age benefit from vet checkups at least every 6 months, including bloodwork and blood pressure checks.

Many indoor cats live into their mid-to-late teens, and some past 20. A 2024 UK study found an average life expectancy of 11.74 years across all cats. Indoor living avoids many risks such as traffic and fights.

Look at the teeth (baby teeth in young kittens, adult teeth by about 6 months, more tartar and wear with age), the eyes (blue in young kittens, cloudier in seniors), the coat and muscle tone. A vet exam gives the best estimate.

In the 2024 VetCompass study, Burmese cats had the longest life expectancy at 14.42 years. The Sphynx had the shortest at 6.68 years.

On average, yes. In the 2024 UK study, female cats lived about 16 months longer than males.

All cats should have at least one exam a year. Senior cats over 10 should be seen at least every 6 months, and more often if they have chronic conditions.

Both age quickly at first, but dog aging depends heavily on size, and large dogs age faster. Cats age more uniformly. Use the dog age calculator to compare.

Manzoor Ahmad

Pharmacist & health writer · 13+ years of web development and SEO experience

Manzoor is a pharmacist with more than nine years of experience writing evidence-based health and supplement content. He builds every dexocalc pet calculator from primary veterinary references. The life stages in this tool follow the 2021 AAHA/AAFP Feline Life Stage Guidelines, and the lifespan figures come from the Royal Veterinary College’s 2024 VetCompass study. This calculator is for education and planning. It does not replace your veterinarian.

Sources

Disclaimer: Cat-to-human age conversions are approximations based on widely used veterinary patterns, and individual cats age differently. Unknown-age estimates are rough. This tool is educational and does not replace a veterinary examination.