What is a reverse pregnancy calculator?

The conception calculator allows you to calculate the exact day of conception based on the weeks' gestation and the delivery date. Conception, the fertilization of the egg by the sperm usually happens 266 days before the due date. The pregnancy due date is calculated 266 days after ovulation conception and fertilization. It's based on either your due date or the actual delivery date and it will calculate back to around the time of conception to help you find out about when you may have conceived.

You can calculate this date more than 100 years in the past. Just enter the actual birthday of the baby and the weeks of pregnancy, and it will automatically calculate a range of dates when sex likely happened, when the baby was conceived, and the implantation date range.