Pregnancy Due Date Calculator
Calculate your estimated due date and key pregnancy milestones.
About Pregnancy Due Date Calculation
An estimated due date (EDD) is calculated based on the Naegele's rule — the most widely used method — which adds 280 days (40 weeks) to the first day of your last menstrual period (LMP). This assumes a 28-day cycle; this calculator adjusts the EDD for different cycle lengths. Pregnancy is divided into three trimesters: the first trimester runs from conception to week 12, the second from weeks 13–27, and the third from week 28 until birth.
Only about 4% of babies are born exactly on their due date. Most births occur within two weeks either side. This tool is for informational purposes only — always confirm your due date with a qualified healthcare provider. Ultrasound measurements in early pregnancy provide the most accurate dating.
How to Use
- Choose your calculation method: last menstrual period, conception date, or IVF transfer date.
- Enter the relevant date using the date picker.
- For the LMP method, enter your average cycle length (default 28 days).
- Click ✨ Calculate to see your due date, current week, trimester, and key milestone dates.