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Dog Pregnancy Calculator
Find out when your dog's puppies are due. Enter the mating date to get the estimated whelping date, the normal 58 to 68 day window, key vet check dates and a week-by-week calendar of what happens during dog pregnancy.
If she was bred more than once, use the first date and allow a few extra days.
Enter your values to see the result.
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How to use the Dog Pregnancy Calculator
- Enter the mating date. If she was bred several times, use the first date.
- Press Calculate due date to see the estimated due date and the normal whelping window.
- Check today's status: the day and week of pregnancy and how many days are left.
- Use the calendar to plan the vet visits, the food change and the whelping box set-up.
- Download or copy the calendar to share it with your vet or family.
How the due date is calculated
Due date = mating date + 63 days. The normal whelping window is day 58 to day 68 after mating. For example, a dog bred on March 1 is due around May 3, with puppies likely between April 28 and May 8 (in a non-leap year).
Breeders who use progesterone or LH testing can be more precise: whelping usually happens 63 days after ovulation or 65 days after the LH surge, give or take a day.
Dog pregnancy timeline
| Day | Milestone |
|---|---|
| 0 | Mating |
| 16 – 20 | Embryos implant in the uterus |
| 25+ | Ultrasound can detect pregnancy and heartbeats |
| 28 – 30 | Vet may feel the fetuses by palpation |
| 35 – 42 | Gradual switch to puppy or growth food |
| 45+ | Skeletons visible on X-ray: count the puppies |
| 50 – 56 | Prepare and introduce the whelping box |
| 56+ | Take her temperature twice a day |
| 58 – 68 | Normal whelping window (63 on average) |
This calendar is general information. Every pregnancy is different, so keep your vet involved, especially for first-time mothers, very small or brachycephalic breeds, and large litters.
Frequently asked questions
How long are dogs pregnant?
Dog pregnancy lasts about 63 days (9 weeks) from mating, with a normal range of about 58 to 68 days. Counted from the LH hormone surge measured by a vet, it is very consistent at 65 days, plus or minus 1 day.
Why can the due date vary by several days?
Sperm can survive in the female for 5 to 7 days and eggs need a couple of days to mature after ovulation, so conception may happen days after mating. That is why a due date counted from mating has a range rather than one exact day.
How can I tell if my dog is pregnant?
Early signs are subtle. A vet can confirm pregnancy by ultrasound from about day 25, by feeling the abdomen around day 28, by a relaxin blood test from about day 25 to 30, or by X-ray after day 45, which also shows how many puppies there are.
How do I know labor is close?
Most dogs' rectal temperature drops below about 99 °F (37.2 °C) 12 to 24 hours before labor. Other signs are restlessness, nesting, panting, refusing food and shivering. Start taking her temperature twice a day from about day 56.
When should I call the vet?
Contact your vet if there are no puppies by day 68 to 70, if she strains hard for 30 to 60 minutes without producing a puppy, if more than 2 to 4 hours pass between puppies while more are expected, or if there is green or bloody discharge before the first puppy.
Should a pregnant dog eat more?
Food needs stay about the same for the first 4 to 5 weeks, then rise steadily. Most vets recommend switching gradually to a puppy or growth formula from around week 5 or 6, feeding smaller, more frequent meals near the end.
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