If you know the date of conception FOR SURE how can figure out your due from that All calculators put my based on cycle wrong therefore is wrong?

To calculate your due date based on the date of conception, follow these steps:

1. Add 280 days (40 weeks) to the date of conception. This will give you the expected date of delivery.

2. If the date of conception falls on a leap day (February 29), add 279 days (39 weeks and 6 days) instead.

3. Keep in mind that this calculation is based on an average menstrual cycle and the actual length of pregnancy can vary from woman to woman. The due date is an estimated date and it's possible to give birth a few days or even a few weeks before or after the due date.

If you're unsure about the exact date of conception, you can use an ultrasound to estimate the gestational age of the fetus and calculate the due date based on that.