Pregnancy Due Date Calculator
Estimate your pregnancy due date based on your last menstrual period or conception date.
See your current week and trimester.
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Estimated Due Date
Pregnancy due date is estimated using Naegele’s Rule:
From Last Menstrual Period (LMP):
Due Date = LMP + 280 days (40 weeks)
From Conception Date:
Due Date = Conception Date + 266 days (38 weeks)
Trimesters:
- First trimester: Weeks 1–12
- Second trimester: Weeks 13–26
- Third trimester: Weeks 27–40
Important notes:
- Only about 5% of babies are born on their exact due date
- A normal full-term pregnancy ranges from 37 to 42 weeks
- This calculator provides an estimate — your healthcare provider may adjust the date based on ultrasound measurements
- The LMP method assumes a regular 28-day cycle with ovulation on day 14