Free breeder tool

Whelping Date Calculator

When are the puppies due? Calculate from the ovulation date, LH surge, or breeding date — with the full pregnancy timeline from ultrasound to the temperature drop.

Gestation from ovulation is 63 ± 1 days — the most precise method.
The due date appears here

Pick the date you know — ovulation gives the tightest prediction — and we'll map the due date plus the ultrasound, X-ray, and temperature-watch windows.

Why the ovulation date beats the breeding date

Canine gestation is one of the most predictable in veterinary medicine — 63 ± 1 days from ovulation, or 65 ± 1 days from the LH surge that precedes it. The famous “57 to 72 days” range you'll see quoted everywhere isn't biological variation: it's measurement error, because sperm can wait up to a week for ovulation after a breeding. If your repro vet ran progesterone timing, you already have the precise anchor — use it here and your due date is accurate to about a weekend.

The pregnancy timeline breeders plan around

  • Day 25–35 — ultrasound. Confirm the pregnancy and get a rough (not exact) idea of litter size.
  • Day 45 — skeletons mineralize. X-rays become possible from here.
  • Day 55+ — the X-ray count. The accurate puppy count that tells you when whelping is actually done on the night.
  • Day 58 onward — temperature watch. Twice-daily rectal temps; a sustained drop below ~99°F usually means puppies within 12–24 hours.

Common questions

How long are dogs pregnant?

Measured from ovulation, canine pregnancy is remarkably consistent: 63 days, give or take about one. Measured from a breeding date it only looks variable (anywhere from 57 to 72 days) because sperm can survive up to a week in the reproductive tract waiting for ovulation — the pregnancy itself is the same length.

Which date gives the most accurate due date?

Ovulation date from progesterone testing, by far — it pins whelping to a two-to-three-day window. The LH surge date is nearly as good (whelping follows it by 65 ± 1 days). A breeding date alone leaves a roughly ten-day window.

When can pregnancy be confirmed?

Ultrasound is reliable from about day 25–30 after ovulation. Relaxin blood tests work in a similar window. X-rays only become useful after day 45, when puppy skeletons mineralize — and day 55 or later is the best time to count puppies accurately.

How do I know whelping is about to start?

Track her rectal temperature twice daily from about day 58. A sustained drop below roughly 99°F (37.2°C) usually means labor within 12–24 hours. Nesting, restlessness, and refusing food are the other classic signs.

Nine weeks is exactly enough time to fill the litter

Breeders on Whelpify open the waitlist the day the ultrasound confirms — litter page live, applications flowing, deposits collected — so every puppy has a family before go-home day.

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