Dog Pregnancy Calculator
Use 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.
Confirmed ovulation supports a 62–64 day planning window. Pregnancy is recorded as veterinarian-confirmed.
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.
Sources & scope
The calculation guide and this source trail show what the result means, where the rule came from and when it was last reviewed. This is source-and-calculation QA, not a claim of medical, legal, tax or other professional review; time-sensitive decisions still belong with the linked authority.
A visible path from input to answer.
Use tested ovulation, an LH peak or a mating record to build the correct whelping range, veterinary imaging checkpoints and symptom override. The page keeps the calculation scope and its limits beside the result so the output can be checked, copied or revisited.
- Read the record. The calculator uses Known reproductive date, What does that date represent?, Check date, Pregnancy status and Current condition supplied in the form.
- Apply the scope. It applies the Global veterinary planning — Merck reproductive timing and diagnosis references reference and the explicit date, unit and counting conventions shown in the result.
- Expose the checkpoints. Intermediate rows, warnings and timeline events stay visible; the emphasized row identifies the primary checkpoint when one exists.
Confirmed ovulation supports a 62–64 day planning window. Pregnancy is recorded as veterinarian-confirmed.
- Whelping planning windowOct 31, 2026 – Nov 2, 2026
- Ultrasound referenceSep 24, 2026 – Oct 4, 2026
- Current timingBefore the usual ultrasound-detection window
Calculation purpose: Use tested ovulation, an LH peak or a mating record to build the correct whelping range, veterinary imaging checkpoints and symptom override. This is a conditional reference output; the linked source and the situation-specific facts control the decision.
Calendar inputs use plain year-month-day semantics. Leap days, month ends, date-pair order and unsupported dates are checked before the result is shown.
Rule set 2.0.0 · Last reviewed 2026-08-20 · Next review due 2027-02-20. The source panel below contains the linked evidence.
Plan the next pet preventive reminder.
Copy the interval from the exact product label or your veterinarian’s plan. This helper schedules that interval; it does not recommend a medication or frequency.
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.