Pregnancy Due Date Calculator

Pick a method. We do the date math and show your estimated due date, current gestational age, trimester, timeline, and a calendar file you can save.

Method

First day of last period

Average cycle length (days)

We adjust EDD by (cycle − 28) days

Standard dating uses 40 weeks from LMP for a 28 day cycle. We adjust for different cycle lengths.
Ultrasound-based dating is often used when it differs from LMP. This tool shows a single estimate and does not replace clinical advice.
Trimester definitions vary slightly. We use: 1st 0–12w6d, 2nd 13–27w6d, 3rd 28w+.
Always consult a clinician for personal medical decisions.