Calculate your kitten's age in weeks, months, and cat years â and see which development stage they're in.
Enter your kitten's birth date â or estimate from weight â to see their exact age, cat-year equivalent, and next milestone
This calculator converts your kitten's age into weeks, months, and cat years using the standard cat-age guideline: the first year of a cat's life is roughly equal to 15 human years, the second year adds about 9 more, and each year after that adds about 4.
Enter your kitten's birth date for the most precise result, or pick the weight range that matches your kitten and we'll estimate from there.
Kittens grow incredibly fast. Here is the typical timeline of kitten stages and what to expect at each one.
| Age | Stage | Key Milestones |
|---|---|---|
| 0â2 weeks | Newborn | Eyes closed, ears folded, nursing, sleeping most of the day. |
| 2â3 weeks | Transitional | Eyes open, ears begin to unfold, first wobbly steps, starts responding to sounds. |
| 3â8 weeks | Socialization | Weaning begins, litter box training, play with littermates, first vaccinations. |
| 2â6 months | Juvenile | Baby teeth replaced by adult teeth, vaccinations continue, big growth spurt. |
| 6â12 months | Adolescent | Sexual maturity, full adult size, high energy and playfulness. |
| 1â3 years | Young Adult | Adult behavior and temperament established. |
See your kitten's age in the units vets and breeders actually use.
Understand your kitten's life stage compared to a human's.
From newborn to young adult â know what to expect at every phase.
Time vaccinations, deworming, and vet visits to your kitten's stage.