A 1 month old kitten is about 1 in human years, 4 months ≈ 6, 6 months ≈ 10, 10 months ≈ 13.3, and 12 months ≈ 15 human years.
How old is my kitten in human years?
Cats race through childhood even faster than dogs. By its first birthday a cat is physically and sexually mature — roughly equal to a 15-year-old teenager. By age 2 it's a young adult of about 24. That's why the "multiply by seven" rule badly underestimates kittens: it says a 6-month-old kitten is 3½, when developmentally it's closer to 10.
This cat months to human years calculator uses the standard feline age chart used by vets and pet organizations:
Between those points we interpolate smoothly, so you get a sensible answer for any month — like a 7 month old cat or a 10 month old kitten.
Cat months to human years chart
| Cat age | Human years | AAHA/AAFP life stage |
|---|---|---|
| 1 month | 1 | Kitten |
| 2 months | 2.5 | Kitten |
| 3 months | 4 | Kitten |
| 4 months | 6 | Kitten |
| 5 months | 8 | Kitten |
| 6 months | 10 | Kitten |
| 7 months | 10.8 | Kitten |
| 8 months | 11.7 | Kitten |
| 9 months | 12.5 | Kitten |
| 10 months | 13.3 | Kitten |
| 11 months | 14.2 | Kitten |
| 12 months | 15 | Young adult |
| 13 months | 16 | Young adult |
| 14 months | 17 | Young adult |
| 15 months | 18 | Young adult |
| 16 months | 19 | Young adult |
| 17 months | 20 | Young adult |
| 18 months | 21 | Young adult |
| 19 months | 21.5 | Young adult |
| 20 months | 22 | Young adult |
| 21 months | 22.5 | Young adult |
| 22 months | 23 | Young adult |
| 23 months | 23.5 | Young adult |
| 24 months | 24 | Young adult |
What's happening at each age?
- 0–2 months: eyes open, first teeth, first steps, weaning. A 1 month old cat is like a 1-year-old toddler.
- 2–6 months: rapid growth and play; adult teeth arrive from about 3–4 months. A 4 month old kitten is around 6 in human years.
- 6–12 months: the "teen" phase. Many kittens reach sexual maturity as early as 4–6 months, so ask your vet about spay/neuter timing. A 10 month old cat is about 13.3.
- 12–24 months: young adulthood. The 2021 AAHA/AAFP guidelines count cats as "young adults" from 1 to 6 years.
Need the other direction or an older cat? Try the senior cat age calculator, or estimate an unknown birthday with the kitten age estimator.
Frequently asked questions
How old is a 4 month old cat in human years?
A 4 month old cat is about 6 human years old — like a young school-age child.
How old is a 6 month old kitten in human years?
A 6 month old kitten is about 10 human years old.
How old is a 7 month old cat in human years?
About 10.8 human years.
How old is a 10 month old cat in human years?
A 10 month old cat is about 13.3 human years old — a young teenager.
How old is a 1 month old kitten in human years?
A 1 month old kitten is roughly 1 human year old — a toddler just learning to walk and play.
How old is an 8 or 9 month old kitten in human years?
An 8 month old kitten is about 11.7 and a 9 month old kitten about 12.5 human years old.
How do you convert cat months to human years?
Use the feline chart: 1 month ≈ 1, 3 months ≈ 4, 6 months ≈ 10 and 12 months ≈ 15 human years, then estimate in between. The calculator above does this for you.
At what age is a kitten considered an adult cat?
The AAHA/AAFP Feline Life Stage Guidelines define kittens as birth to 1 year. From 1 to 6 years a cat is a young adult.
This calculator gives an estimate for education and fun. Every pet ages differently — for health decisions, talk to your veterinarian.