Pregnancy Due Date Calculator
Calculate due date, current week, and key pregnancy milestones
Estimated Due Date (EDD)
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Current week
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Current trimester
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Days pregnant
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Weeks remaining
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Key milestones
End of 1st trimester (Week 13)—
Anatomy scan (Week 20)—
End of 2nd trimester (Week 27)—
Full term (Week 37)—
Due date (Week 40)—
About Due Date Calculation
How is the due date calculated?
The standard method (Naegele's rule) adds 280 days (40 weeks) to the first day of the last menstrual period. This assumes a 28-day cycle. For longer or shorter cycles, the ovulation date is adjusted accordingly.
How accurate is the due date?
Only about 5% of babies are born on their exact due date. Most babies arrive within 2 weeks before or after the EDD. An ultrasound scan in the first trimester gives the most accurate due date.