Cat Age Calculator
Cats reach maturity quickly: the first year is worth about 15 human years, the second adds 9, and each additional year adds roughly 4 human years.
A 3-year-old cat is about 28 in human years.
Conversion chart
| Cat years | Human years |
|---|---|
| 1 | 15 |
| 2 | 24 |
| 3 | 28 |
| 4 | 32 |
| 5 | 36 |
| 6 | 40 |
| 7 | 44 |
| 8 | 48 |
| 9 | 52 |
| 10 | 56 |
| 11 | 60 |
| 12 | 64 |
| 13 | 68 |
| 14 | 72 |
| 15 | 76 |
| 16 | 80 |
| 17 | 84 |
| 18 | 88 |
| 19 | 92 |
| 20 | 96 |
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About this tool
Cats reach maturity quickly: the first year is worth about 15 human years, the second adds 9, and each additional year adds roughly 4 human years. For your exact age in years, months and days use the age calculator. Related tools: date calculator, time calculator, day of the week, event countdowns.
Frequently asked questions
How do you convert cat years to human years?
Allow 15 human years for the first year, 9 more for the second (24 total), then about 4 human years for each additional year. A 10-year-old cat is around 56 in human years.
When is a cat considered a senior?
Most cats are considered mature at 7, senior at 11 and geriatric from around 15 — though indoor cats often live well into their late teens.
Do indoor and outdoor cats age differently?
Indoor cats generally live longer because they face fewer accidents and diseases. The formula here describes average ageing and does not separate indoor from outdoor cats.