Pregnancy Calculator

How is Pregnancy Calculated?

Pregnancy is typically calculated from the first day of your last menstrual period (LMP). The average pregnancy lasts about 40 weeks (280 days) from the LMP. This calculator estimates your due date based on this method.

Due Date Formula

Due Date = LMP + 280 days (40 weeks)

Example Calculation

If your last period started on January 1, 2024:

LMP = Jan 1, 2024
Due Date = Jan 1, 2024 + 280 days = October 7, 2024

FAQs

  • How accurate is the due date?
    The due date is an estimate. Most babies are born within 2 weeks before or after the due date.
  • Can I use conception date instead?
    Yes, but LMP is more commonly used. Conception usually occurs about 2 weeks after LMP.
  • What if my cycles are irregular?
    The calculator assumes a 28-day cycle. If your cycles are longer or shorter, your due date may vary.

Pregnancy Calculator