Pet Calculators
Dog & cat due date.
Dogs carry for about 63 days from ovulation and cats about 65 days from breeding. Enter the date to see the expected due date, the likely window and when a vet can confirm and count. Runs in your browser.
Dates
Due date
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Worked example
A dog first bred on 2026-03-01: 63 days later is 2026-05-03, with births possible from about 2026-04-28 to 2026-05-08. A vet can confirm by ultrasound around 2026-03-29 (day 28) and count puppies by X-ray from about 2026-04-15 (day 45). If the date is a progesterone-confirmed ovulation instead, the window narrows to 2026-05-02 to 2026-05-04.
How it works
Dog gestation is about 63 days from ovulation, with a narrow window of one or two days either side. Counted from the first breeding the spread is wider, about 58 to 68 days, because sperm survive for days and eggs mature after ovulation. Progesterone testing to pinpoint ovulation gives the most accurate date. Cats are about 65 days from breeding (63 to 67 is the window used here).
A vet can confirm pregnancy by ultrasound from about day 25 to 28, and count puppies by X-ray after about day 45, when the skeletons have mineralised. Call your vet about the due date, signs of trouble such as green discharge before a puppy, hard straining for more than 30 to 60 minutes without a puppy, or going past the window. Many dogs have a drop in body temperature about 12 to 24 hours before whelping.
Sources and basis (checked 2026-10-05): Merck Veterinary Manual, Management of Reproduction in Dogs (pregnancy lasts about 62 to 64 days; this tool uses 63). Cat dates are a rough planning window. Windows are averages: individual pregnancies vary.
FAQ
How long are dogs pregnant?
About 63 days from ovulation. Counted from the first breeding, births occur from about day 58 to 68.
How long are cats pregnant?
About 65 days from breeding, with a typical range of about 63 to 67 days.
When can a vet confirm a dog is pregnant?
Ultrasound can confirm pregnancy from about day 25 to 28. An X-ray after about day 45 can count puppies.
How can I tell my dog is about to give birth?
Nesting, restlessness, loss of appetite and a drop in body temperature about 12 to 24 hours before whelping are common. Ask your vet what to expect for your breed.
What if my dog goes past her due date?
Call your vet if she is more than a day or two past the window, or sooner if she is unwell, has discharge, or is straining without producing a puppy.
Disclaimer
Not veterinary advice. These dates are averages and cannot predict an individual birth. Work with your vet during a pregnancy, and call a vet urgently if your pet seems unwell, strains without producing a young or has green or bloody discharge before birth.