Due Date Calculator
Estimate a due date and pregnancy week from last menstrual period or conception date using common calendar rules. Not medical advice — talk to a clinician.
Frequently asked questions
How is the due date estimated?
From last period the tool adds 280 days (Naegele). From conception it adds 266 days. Real pregnancies vary — confirm with a clinician.
Is this medical advice?
No. It is an educational calendar estimate only — not a diagnosis or medical advice.