CollarCat Calculators for Every Stage
Free tools for cat parents and breeders: estimate your cat's pregnancy due date, predict a kitten's adult size, explore coat color genetics, and convert her age into human years.
Choose Your Cat Calculator
Each tool gives a clear estimate with an honest range, plus a reminder to check with your vet.
Cat Pregnancy & Gestation
Estimate her due date and kittening window from the mating date, with a week-by-week guide.
Open calculatorCat Coat Color Genetics
Predict kitten coat colors and patterns, including tortoiseshell and the X-linked orange gene.
Open calculatorCat Growth
Predict a kitten's adult size and weight from its current age, weight, and breed.
Open calculatorCat Age
Convert your cat's age into human years with the standard feline aging formula.
Open calculatorHow the Tools Connect
The calculators follow your cat's journey, from a new litter to a full-grown adult.
Coat Color Genetics
Curious what a litter might look like? Predict the kittens' possible colors and patterns from the parents' genes.
Pregnancy & Kittening
Once she is expecting, calculate the due date and kittening window and follow the week-by-week timeline.
Kitten Growth
After the litter arrives, estimate how big each kitten will grow as an adult.