Dog Pregnancy Calculator

How to use the Dog Pregnancy Calculator#

1. Enter the breeding date. Use the date of mating, or of insemination.
2. Check the length. Leave the average, or enter your vet’s figure for the breed.
3. Read your dates. You get the expected date, the likely window and your dog’s progress.

How long is a dog pregnant?#

The usual figure is about 63 days from ovulation. Counted from the mating date, it can run from about 58 to 68 days, because the egg isn’t always ready on the day of mating. If your vet tracked ovulation with hormone tests, ask them for the due date.

Getting ready for the puppies#

Set up a whelping box in a quiet place two weeks or so before the due date, and let her get used to it. Her body temperature often drops in the day before labour, so some owners take it twice a day near the end. Ask your vet to explain what to watch for.

Vets often confirm pregnancy with ultrasound from around four weeks after mating, and can count puppies by X-ray late in pregnancy. Call a vet at once if she strains hard for a long time with no puppy, or if she has green discharge before the first puppy.

Why the date is a window#

A dog’s due date depends on what you count from. From ovulation it is about 63 days, but from the day of mating it can fall anywhere from 58 to 68, because the egg is not always ready when the dogs mate. If your vet tracked ovulation with hormone tests, use their date instead of this one. This calculator is a planning tool and doesn’t replace veterinary advice.

A worked example#

A bitch is mated on Tue 6 April 2027. With the default of 63 days the due date is Tue 8 June 2027. Because sperm can survive in her for several days, and ovulation does not line up neatly with the mating, the likely window is wider than for most species: Thu 3 June 2027 to Sun 13 June 2027. The halfway point is Sat 8 May 2027 and the final stretch begins on Sun 30 May 2027.

Counting from ovulation rather than from mating#

The 63 days people quote is really measured from ovulation, give or take a day. A dog’s eggs mature after they are released, and the fertile period can be several days long, so mating on the wrong side of ovulation shifts the date. That is why the same bitch can whelp anywhere from day 58 to day 68 counted from the mating.

If your vet ran progesterone tests to time the breeding, ask which day they count as ovulation and enter that date instead. Use 63 days from it. Breeders who do this often see whelping within a day or so of the prediction, which makes the late nights easier to plan.

Checks and signs as the date approaches#

Ultrasound can show heartbeats from about day 25 to 30, and a blood test for relaxin works from around the same time. An X-ray late in pregnancy, from about day 55, is the usual way to count puppies, so you know when she has finished whelping.

In the final week her appetite may drop and she will start nesting. A common sign that whelping is within about a day is a fall in rectal temperature below roughly 37.2 °C (99 °F) from her usual 38.3 to 39.2 °C. Take it twice a day from about day 58, which is Thu 3 June 2027 here.

Call the vet if she is straining hard for an hour without producing a puppy, if more than two hours pass between puppies while she is clearly still in labour, or if she passes green discharge before the first puppy has arrived.

Small and large breeds differ#

Litter size matters in dogs more than most people expect. A toy breed with two or three puppies may go to the later end of the window, while a large breed with ten or more often whelps earlier. Brachycephalic breeds such as bulldogs and pugs frequently need a planned caesarean, and the date for it is chosen by the vet, from hormone tests, not by counting days alone.

Last reviewed October 2026 by the Calclulo team.