Dog Whelping Date Calculator
Estimate your dog's due date and map the key pregnancy milestones from the mating, ovulation, or LH-surge date — using real veterinary gestation timings.
Please choose a reference point.
Please enter a valid date within the last or next 12 months.
Pregnancy timeline & care milestones
Overview
The Dog Whelping Date Calculator helps breeders, owners of a pregnant bitch, and veterinary staff estimate when a litter is likely to arrive and what to prepare for along the way. Canine pregnancy is short and moves fast — roughly nine weeks from conception to whelping — so knowing your dates lets you schedule ultrasounds, X-rays, and around-the-clock supervision at exactly the right time.
Rather than returning a single guessed date, the tool anchors its math to the reference point you actually have — the first mating, a progesterone-confirmed ovulation, or the LH surge — because each carries a different level of precision. It then lays out the whole timeline: implantation, the earliest reliable ultrasound, the X-ray puppy-count window, temperature monitoring, and the expected whelping day.
How It Works
- Choose your reference point. Pick whichever event you have a confident date for. Ovulation (from progesterone testing) is the most accurate; a single mating date is the least precise.
- Enter the date of that event using the date picker.
- Click “Calculate Due Date.” The tool computes the estimated whelping date, the likely date window, and a full care timeline.
- Review the breakdown and note the milestone dates in your calendar. Use “Reset” to clear everything and start a new calculation.
Formula Explanation
Canine gestation is most consistent when measured from ovulation — almost always 63 days (± 1). The other reference points are converted to that same biological clock:
Due date = Ovulation date + 63 days (window 62–64)Due date = LH date + 65 days (ovulation ≈ LH + 2, window 64–66)Due date = Mating date + 63 days (window 58–68)The wider 58–68 day window for a mating date reflects reality: sperm can survive for several days in the reproductive tract and the eggs still need to mature, so the gap between mating and actual conception varies. Milestone dates (implantation, ultrasound, X-ray, temperature drop) are all counted forward from the estimated ovulation date, which is why every method is normalised back to it.
Practical Benefits
- Book veterinary visits on time — schedule the confirmation ultrasound around day 25–30 and the puppy-counting X-ray from day 55.
- Never miss the whelping — begin twice-daily temperature checks about a week out; a drop below ~37.2 °C (99 °F) usually signals labour within 24 hours.
- Prepare the whelping box early so the bitch can settle and nest before contractions begin.
- Plan supplies and support — line up help, heat sources, and emergency vet contacts before the due window opens.
Frequently Asked Questions
A single mating date gives only a rough estimate. Because a bitch can conceive several days before or after mating, whelping can occur anywhere from 58 to 68 days later. For a tighter prediction, ask your vet for progesterone testing to pinpoint ovulation, which narrows the window to about 63 days ± 1.
Unlike mating, ovulation is a fixed biological event. Dogs consistently whelp about 63 days after ovulation regardless of when mating happened. Progesterone blood tests (or an LH-surge test) let your vet identify that day, which is why breeders rely on it for the most dependable due dates.
Ultrasound can typically confirm pregnancy from about day 25–30 and check for foetal heartbeats. To count puppies reliably, an X-ray is best from around day 55, once the puppies' skeletons have calcified enough to be visible. The calculator flags both of these windows on your timeline.
In the last week, take the bitch's rectal temperature twice daily. A clear drop below roughly 37.2 °C (99 °F) usually means labour will begin within about 24 hours. Other signs include restlessness, nesting, refusing food, and panting. If active straining lasts more than an hour without a puppy, contact your vet immediately.
