KibbleMath

Dog pregnancy calculator

The expected whelping date — 63 days from mating or ovulation — plus the milestone dates worth putting in your calendar.

expected whelping

How dog pregnancy timing works

Gestation in dogs is remarkably consistent from ovulation: about 63 days (62–64). Counted from mating it looks messier — anywhere from 58 to 68 days — not because pregnancies vary that much, but because sperm can survive several days waiting for ovulation. That's why the calculator shows a wider window for mating dates and a tight one for vet-confirmed ovulation.

The checkpoints along the way

Days 25–30: pregnancy can be confirmed — a relaxin blood test from about day 25, or ultrasound showing heartbeats. Around day 40: appetite and belly grow; switch gradually toward a higher-energy food per your vet's advice. Day 55+: an X-ray can count skeletons, so you know how many puppies to expect on the night. Day 56 onward: take rectal temperature twice daily — a drop below ~37.2 °C (99 °F) typically means labor within 24 hours.

When to call the vet during whelping

Keep the emergency number ready and call if: the due window passes with no labor, there's strong straining for 30+ minutes without a puppy, more than 2 hours pass between puppies while she's clearly still in labor, or you see green-black discharge before the first puppy arrives. Quick calls are never wrong here.

Breeding is a vet-partnership sport. This calculator organizes the timeline — it doesn't replace progesterone testing, pregnancy confirmation or a whelping plan made with your veterinarian.

Frequently asked questions

How long are dogs pregnant?

About 63 days from ovulation. From mating, anywhere between 58 and 68 days is normal — the spread reflects sperm surviving until ovulation, not true differences in pregnancy length.

How soon can I confirm my dog is pregnant?

From about day 25: a relaxin blood test or ultrasound (which also shows heartbeats around days 25–30). Abdominal palpation by a vet works around days 28–35. An X-ray from day 55 gives the best puppy count.

What are the signs labor is starting?

The most reliable early signal is the temperature drop below ~37.2 °C within 24 hours of labor, alongside nesting, restlessness, panting and refusing food. Stage-two labor — active contractions — should produce a puppy within about 30 minutes; if not, call your vet.