How long is a dog's pregnancy?

Canine gestation averages about 63 days from ovulation, but timing from the mating date ranges from 58 to 68 days because sperm can survive several days before fertilisation. The calculator shows a 58 to 65 day window from the breeding date with 63 days as most likely.

Why is the due date a range, not one day?

Fertilisation may happen days after mating, and gestation length naturally varies between individuals and litters. Giving a range from the shortest to the longest typical gestation is more realistic and helps you prepare a whelping or kindling area in good time.

What gestation periods does it cover?

It includes dogs (58–65 days), cats (58–67), rabbits (28–31), guinea pigs (59–72), ferrets (41–42), Syrian hamsters (16–18), and horses (320–362). Each uses published reference ranges with a typical midpoint.

When should I worry about an overdue pet?

If labour has not begun by the latest date in the range, contact your vet. Overdue pregnancy can signal a problem such as a stuck or oversized fetus, low litter number, or miscalculated dates, and may need veterinary intervention.

How can I confirm pregnancy and timing?

A vet can confirm pregnancy by ultrasound from around day 25 to 35 in dogs and cats, and estimate due date more precisely with measurements. This calculator gives a planning window; veterinary imaging gives a firmer date.

Pet Gestation & Due Date Calculator

Plan ahead for whelping, kindling, and kittening

Knowing roughly when a litter is due lets breeders prepare a clean, quiet nesting area, line up help, and watch for problems. This calculator applies the standard gestation range for each species to your breeding date and returns the earliest, most likely, and latest expected birth dates.

How it works

Each species has a documented gestation range — a minimum, a typical value, and a maximum number of days from conception. Because the exact moment of fertilisation is rarely known, the tool counts from the breeding (mating or insemination) date and adds the minimum, average, and maximum days:

earliest due = breeding date + minimum gestation days
likely due   = breeding date + typical gestation days
latest due   = breeding date + maximum gestation days

For example dogs use 58, 63, and 65 days; cats 58, 65, and 67; rabbits 28, 31, and 31. The result is a window rather than a single day, which reflects biological reality far better than a fixed count.

Tips

Set up the nesting box at least a week before the earliest date so the mother can settle in. In the final days, a drop in body temperature (about one degree in dogs) often precedes labour within 24 hours. If the latest date passes with no signs of labour, call your vet promptly — an overdue delivery is a common reason for intervention.

Notes

These ranges are general references for healthy pregnancies. Breed, litter size, and individual variation all shift the timing. Veterinary ultrasound from around day 25 to 35 confirms the pregnancy and tightens the estimate.