Pets, reproduction and life stages · Calculator

Dog Pregnancy Calculator
without the guesswork.

Dog Pregnancy Whelping Calculator — Use tested ovulation, an LH peak or a mating record to build the correct whelping range, veterinary imaging checkpoints and symptom override. Uses a focused calculator with visible assumptions. Inputs stay in your browser.

Reference toolDog Pregnancy Whelping CalculatorUse tested ovulation, an LH peak or a mating record to build the correct whelping range, veterinary imaging checkpoints and symptom override. Inputs stay in your browser.
Reference calculation
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Fri, Aug 21, 2026
Use the date documented by your veterinarian or breeding record.
Breeding dates are less closely related to whelping than tested ovulation or LH timing.
Fri, Aug 21, 2026
A concerning condition overrides every calendar estimate.

Plain-date semantics · start date is not counted unless the result explicitly says inclusive.

Your result
Oct 22, 2026 – Oct 24, 2026

Confirmed ovulation supports a 62–64 day planning window. Pregnancy is recorded as veterinarian-confirmed.

Dating basisConfirmed ovulationMerck gives 62–64 days from tested ovulation.
Known reproductive dateAug 21, 2026
Check dateAug 21, 20260 days after the recorded date
Pregnancy confirmationVeterinarian-confirmed
Whelping planning windowOct 22, 2026 – Oct 24, 2026A planning range, not a guaranteed delivery window
Ultrasound referenceSep 15, 2026 – Sep 25, 2026Merck: reliable detection is commonly possible in this period
Radiograph visibility referenceOct 2, 2026Routine radiography may show fetal skeletons around day 42–45
Litter-size radiograph referenceOct 15, 2026Merck identifies >55 days as the preferred late-gestation timing
Current timingBefore the usual ultrasound-detection window
Sep 15, 2026Ultrasound reference window opens
Oct 2, 2026Radiograph visibility reference
Oct 15, 2026Late radiograph / litter-size reference
Oct 22, 2026Whelping planning window opens
Oct 24, 2026Whelping planning window closes
Calendar options

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Choose a calendar service, then confirm the event. Downloading an .ics file does not add it until you open or import it.

Read before relying

Context matters.

  • A breeding date is not the same as conception or ovulation; fresh canine sperm can remain viable for days, which is why the mating-date range is wider.
  • Do not use an estimated date to schedule an elective procedure or to wait through abnormal labor, severe pain, collapse, heavy bleeding or other distress.
  • Pregnancy diagnosis, fetal viability and delivery decisions belong with a veterinarian.
Rule set 2.0.0

Sources & scope

Verified

This page shows the source trail, jurisdiction and review date alongside the result. Always confirm time-sensitive rules with the linked authority.

JurisdictionGlobal veterinary planning — Merck reproductive timing and diagnosis references
Review date2027-02-21
PrivacyNo input upload
Questions answered

What to know before using the result.

Why is the mating-date window wider than the ovulation window?

A mating date does not establish the conception or ovulation date. Merck gives 58–72 days from breeding at an unknown estrus stage, compared with 62–64 days from tested ovulation.

When can a veterinarian confirm pregnancy or count the litter?

Merck describes reliable ultrasound detection around days 25–35, routine radiographic visibility around days 42–45 and late radiography after day 55 as the preferred time to determine litter size.

Can the calculator tell me whether labor is normal?

No. Severe distress, abnormal discharge or bleeding, collapse, prolonged or abnormal labor and any concern about the dam or puppies require veterinary assessment rather than another date calculation.