Cat Age Calculator
Enter your cat’s birthday to get its exact age in years, months and days, its next birthday, its life stage and its age in human years on the International Cat Care chart.
Cat life stages (2021 AAHA/AAFP): kitten to 1 year, young adult 1–6 years, mature adult 7–10 years, senior over 10 years.
How it works
Life stages follow the 2021 AAHA/AAFP Feline Life Stage Guidelines: kitten (birth to 1 year), young adult (1–6 years), mature adult (7–10 years), senior (over 10 years) and end of life (any age). We also show the International Cat Care stages: kitten (0–6 months), junior (7 months–2 years), adult (3–6 years), mature (7–10), senior (11–14) and super senior (15+).
Human years use the International Cat Care chart. Cats born on 29 February celebrate on 28 February in non-leap years here.
How to use it
- Pick the birthday. Or enter the age in years and months.
- Read the age and stage. Exact age, next birthday, life stage and human years.
Cat life stages
| Stage (AAHA/AAFP 2021) | Age |
|---|---|
| Kitten | Birth to 1 year |
| Young adult | 1–6 years |
| Mature adult | 7–10 years |
| Senior | Over 10 years |
| End of life | Any age |
| Stage (iCatCare) | Age | Human years |
|---|---|---|
| Kitten | 0–6 months | 0–10 |
| Junior | 7 months–2 years | 12–24 |
| Adult | 3–6 years | 28–40 |
| Mature | 7–10 years | 44–56 |
| Senior | 11–14 years | 60–72 |
| Super senior | 15 years + | 76+ |
Frequently asked questions
How do I work out my cat’s age?
Count full years and months since the birthday. The calculator does it for you and handles leap years.
What are the cat life stages?
AAHA/AAFP: kitten (0–1 year), young adult (1–6), mature adult (7–10), senior (over 10), plus end of life at any age. International Cat Care splits these further into kitten, junior, adult, mature, senior and super senior.
How old is my cat in human years?
About 15 at 1 year, 24 at 2, then 4 more for each year: 56 at 10 and 76 at 15.
My cat is a rescue and I don’t know its age. What now?
Ask your vet for an estimate (they look at teeth, eyes and coat), then use the years-and-months option.
When to see a vet
- Your cat is over 10: senior cats benefit from regular check-ups.
- Weight loss, drinking more, vomiting, or changes in grooming or litter-box habits.
- Your cat has stopped eating for more than a day.
This is an estimate for general information, not veterinary advice. Every pet is different. Ask your veterinarian before changing your pet's diet, especially for puppies, kittens, pregnant or nursing pets, seniors, or pets with health conditions.
Sources
- Quimby J, Gowland S, Carney HC, et al. 2021 AAHA/AAFP Feline Life Stage Guidelines. J Feline Med Surg. 2021;23(3):211–233. doi.org/10.1177/1098612X21993657
- AAHA. 2021 AAHA/AAFP Feline Life Stage Guidelines: Feline life stage definitions. www.aaha.org/resources/2021-aaha-aafp-feline-life-stage-guidelines/feline-life-stage-definitions/
- International Cat Care. How to tell your cat’s age in human years (cat age chart). icatcare.org/articles/how-to-tell-your-cats-age-in-human-years
Full methodology: sources and methodology. Last reviewed 20 October 2026.