Cat Age Calculator
A 1-year-old cat is already like a 15-year-old teenager. Enter your cat's age to see the human-year equivalent and which veterinary life stage your cat is in.
How cat years are converted
Cats mature very fast. The commonly used veterinary conversion counts the first year as 15 human years, the second as 9 more (24 total), and about 4 human years for each year after that.
Year 1: 15 · Year 2: 24 · then +4 per year
Example: 12-year-old cat = 24 + (10 × 4) = 64 human years
Cat years to human years chart
| Cat age | Human years | Cat age | Human years |
|---|---|---|---|
| 1 | 15 | 10 | 56 |
| 2 | 24 | 12 | 64 |
| 4 | 32 | 14 | 72 |
| 6 | 40 | 16 | 80 |
| 8 | 48 | 18 | 88 |
Feline life stages
The 2021 AAFP/AAHA Feline Life Stage Guidelines group cats into four age stages plus end-of-life care: kitten (birth to 1 year), young adult (1–6 years), mature adult (7–10 years) and senior (10 years and older). Each stage has different needs for food, vaccines and checkups.
Frequently asked questions
How old is a 15-year-old cat in human years?
About 76 human years (24 + 13 × 4).
When is a cat considered a senior?
From about 10 years old, according to the AAFP/AAHA feline life stage guidelines.
Do indoor cats age differently?
The conversion is the same, but indoor cats usually live longer because they face fewer risks such as traffic, fights and infectious disease.