Pregnancy Due Date Calculator
Calculate your estimated due date using one of the four methods below
Understanding Your Due Date Calculation
Last Menstrual Period (LMP) Method
This is the most common method used by healthcare providers. It assumes a 28-day cycle and calculates 40 weeks from the first day of your last period. This method is most accurate if you have regular menstrual cycles.
Conception Date Method
If you know your conception date, this can provide a more accurate estimate. The calculator adds 266 days (38 weeks) to your conception date to determine your due date.
Ultrasound Method
Early ultrasound dating (before 20 weeks) is considered one of the most accurate methods for determining your due date, especially if your periods are irregular or you're unsure of your LMP.
IVF Transfer Method
For IVF pregnancies, the due date is calculated based on the age of the embryo at transfer and the transfer date. This is typically the most precise method of dating a pregnancy.
Important Notes About Due Dates
- Only about 4% of babies are born on their exact due date
- A normal pregnancy can range from 37 to 42 weeks
- The due date is an estimate, not an exact science
- Consult your healthcare provider for personalized medical advice