Browser-local date calculator · C401
Dog Gestation Calculator
Estimate an approximate whelping window while distinguishing known ovulation timing from a breeding date alone.
Enter the date
Estimated dates
The local calculator is initializing.
Method and sources
The default uses 63 days and shows the source-backed 62–64 days from known ovulation; 58–72 days from first permitted breeding range. Dates are handled as Gregorian civil dates without timezone conversion. Merck Veterinary Manual is the timing source used for this page.
Important: Breeding date and conception or ovulation date are not necessarily the same. The breeding-date window is intentionally broader.
Worked example
From a known ovulation date, the sourced window is 62–64 days. A breeding date alone uses the broader 58–72-day window.
Limitations
These are planning estimates, not guaranteed birth dates or medical thresholds. Species, breed, individual animal, litter or fetal factors, and uncertainty in the starting event can change actual timing. Contact a veterinarian for animal-specific questions.