Cat Pregnancy Calculator: Due Date and Week-by-Week
Enter the date your cat mated to see when her kittens are most likely due, and the dates of the milestones a vet would look for along the way. Gestation figures come from the Merck Veterinary Manual and a peer-reviewed veterinary review.
Checked against 2 sources· Not veterinary advice
How the due date is worked out
The Merck Veterinary Manual says delivery typically happens 64 to 66 days after breeding, so the calculator adds those days to the mating date. It also shows the wider picture from a review of feline pregnancy in Theriogenology: an average of 65.6 days, with a recorded range of 52 to 74 days counted from the first or last mating. The same review notes that pregnancies shorter than 60 days are linked with lower kitten viability.
Cats are induced ovulators, and Merck notes that multiple breedings over 2 to 3 days are recommended, so the breeding date does not always match the conception date. If your cat mated on more than one day, enter the first date and keep the whole window in mind.
Pregnancy milestones, week by week
The calculator lists only milestones with a clear source. Days are counted from mating; the “second half” and “last three weeks” rows assume a pregnancy of about 65 days.
| Day (week) | What happens |
|---|---|
| 21–30 (week 4) | A vet can usually confirm pregnancy. Pregnancy can be detected from about day 21 to 30, by a vet feeling the abdomen (palpation) or by ultrasound. |
| 33+ (week 5) | Second half of pregnancy. If possible, keep her away from other cats during the last half of pregnancy to reduce exposure to infections such as upper respiratory disease. |
| 44+ (week 7) | Last three weeks: more food. She needs about 25% more food during the last 3 weeks of pregnancy. Vets usually recommend a kitten food while she is pregnant and nursing; do not add calcium or vitamin supplements. |
| 56+ (week 9) | X-rays can count the kittens. X-rays taken more than 55 days after breeding can help a vet work out how many kittens to expect. |
| 60+ (week 9) | Kittens born before day 60 are at higher risk. Gestation lengths under 60 days are associated with lower kitten viability, so early labor is a reason to call your vet. |
| 64–66 (week 10) | Typical delivery window. Delivery typically happens 64 to 66 days after breeding. In the first stage of labor (12 to 24 hours) she may hide, be restless, build a nest, vomit, tremble or refuse food. |
Feeding a pregnant and nursing cat
Merck says a pregnant cat needs about 25% more food in the last 3 weeks of pregnancy and 2 to 3 times her usual amount while nursing, and that vets usually recommend a kitten food for both. Merck also advises against giving dietary supplements such as calcium or vitamins. By the time she gives birth, a queen should have gained 12 to 38% of her pre-pregnancy weight (Root Kustritz, 2006). Our cat calorie calculator includes the AAHA factors for pregnancy and nursing.
Labor: the three stages
- Stage I (12 to 24 hours): contractions start but are not visible. She may hide, be restless, build a nest, vomit, tremble or refuse food. Discharge is clear and watery.
- Stage II: visible contractions and the birth of the kittens, usually less than 1 to 2 hours apart.
- Stage III: delivery of the placenta. Cats usually alternate between stages II and III until all kittens are born.
Frequently asked questions
How long is a cat pregnant?
About two months. The Merck Veterinary Manual says pregnancy lasts 60 to 65 days and delivery typically happens 64 to 66 days after breeding. A veterinary review of feline pregnancy reports an average of 65.6 days, with a recorded range of 52 to 74 days.
How can I tell if my cat is pregnant?
A vet can confirm it. According to the Merck Veterinary Manual, pregnancy can be detected from about day 21 to 30 by feeling the abdomen or by ultrasound, and X-rays after day 55 can show how many kittens to expect.
How many kittens do cats usually have?
The average reported litter is 4.0 kittens, though it varies between breeds. The number of matings does not change the litter size (Root Kustritz, 2006).
What are the signs a cat is going into labor?
In the first stage of labor, which lasts 12 to 24 hours, the Merck Veterinary Manual says a queen may hide, become restless and build a nest, and may vomit, tremble or refuse to eat. A clear, watery discharge is normal at this stage.
How long does a cat's labor last?
Stage one lasts 12 to 24 hours. In stage two the kittens are born, usually less than 1 to 2 hours apart. Merck lists labor of more than 24 hours in stage one or two, or more than 1 to 4 hours between kittens, as signs of a difficult birth that needs a vet.
Sources
- Management of Reproduction of Cats (pet owner version), Merck Veterinary Manual. Used for: Pregnancy length, detection, feeding, X-rays and labor.
- Root Kustritz MV. Clinical management of pregnancy in cats. Theriogenology 2006;66(1):145–150, University of Minnesota College of Veterinary Medicine (peer-reviewed review). Used for: Average gestation 65.6 days, range 52–74 days; under 60 days and kitten viability; weight gain.