When Did I Conceive if My Due Date Is September 21?

A calculator that calculates the day of conception based on due date.

If you do not know when you will give birth and you know the date of your last period, use the duea date calculator.

🔮 You seem to want to know the future. You've chosen a delivery date of September 21, 2025. Unfortunately, I can't predict it.

If you want to give birth on September 21, 2025 then you should get pregnant on December 29, 2024, and the first day of your period (L.M.P.) should be December 15, 2024.

Nearest calculation of days of conception based on day of birth