Cat Age Calculator
Find out how old your cat is in human years and which life stage it's in. Enter your cat's age in years; you can use decimals for months.
Age in human years
48 years
Check the highlighted field to see your result.
- Life stage
- Mature adult
- Each year now adds
- 4 years
Results are estimates for information only and do not constitute financial, medical, or legal advice.
How cat years are counted
A cat's first year is roughly 15 human years and the second adds about 9 more, so a 2-year-old cat is like a 24-year-old person. After that, each cat year adds about 4 human years. It's a general guide, not an exact biological age.
Cat life stages
The life stage shown by the calculator follows the2021 AAHA/AAFP Feline Life Stage Guidelines: kitten up to 1 year, young adult from 1 to 6 years, mature adult from 7 to 10 years, and senior over 10 years.
The formula
Human years = 24 + (cat age − 2) × 4
Worked example
Your cat is 8 years old.
- First two years: 15 + 9 = 24 human years.
- The other 6 years: 6 × 4 = 24 human years.
- Total: 24 + 24 = 48 human years, in the mature adult stage.
Frequently asked questions
What are the life stages of a cat?
The 2021 AAHA/AAFP Feline Life Stage Guidelines describe four: kitten (up to 1 year), young adult (1 to 6 years), mature adult (7 to 10 years), and senior (over 10 years).
Do indoor cats age differently?
The way age is counted is the same, but indoor cats often live longer because they face fewer risks such as traffic and fights.
Should older cats see the vet more often?
Many vets suggest more frequent checkups for senior cats, since health problems are more common with age. Ask your vet what is best for your cat.