The average gestation period for dogs is about 63 days from the date of ovulation. However, since the exact ovulation date is often unknown, calculating from the mating date(s) is common. This can lead to a slightly wider range for the due date (typically 58-68 days from the first mating).

No, this calculator provides an estimate based on the average gestation period. Factors like the exact timing of ovulation relative to mating, breed size, and litter size can influence the actual whelping date. It's best used as a guideline.

It's generally recommended to calculate from the first mating date, but be aware that the actual conception could have occurred later. Using the range provided by the calculator helps account for this uncertainty. Consulting a veterinarian for confirmation via ultrasound or X-ray is the most accurate method.