Due Date Calculator
Estimate your pregnancy due date based on the first day of your last menstrual period (LMP) and cycle length.
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FAQ
How is the due date estimated?
A common estimate is 280 days (40 weeks) from the first day of the last menstrual period (LMP). Cycle length can shift the estimate slightly.
Is the due date exact?
No. Many healthy pregnancies deliver before or after the estimated date. It’s a planning estimate.
What if I don’t have a 28‑day cycle?
Adjusting cycle length helps refine the estimate, but an ultrasound is often used for clinical dating.