What Is Naegele's Rule?
Naegele's rule is a standard method of calculating the estimated date of delivery (EDD) by adding 1 year, subtracting 3 months, and adding 7 days to the first day of the last menstrual period (LMP).
Pregnancy Due Date Calculator
Pregnancy Due Date Calculator
Estimated Due Date
October 22, 2026
Conception Date
January 29, 2026
Gestational Age
30 weeks, 0 days
Current Trimester
Third Trimester
This tool provides general information and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider for personal medical decisions.
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Frequently Asked Questions
How is a pregnancy due date calculated?
Naegele's rule calculates due date by adding 280 days (40 weeks) to the first day of your last menstrual period (LMP).
How accurate is an estimated due date?
Only about 5% of babies are born on their exact due date. Most births occur within 2 weeks before or after.
What are the three trimesters?
First trimester: Weeks 1–12; Second trimester: Weeks 13–27; Third trimester: Weeks 28–40+.
Can conception date be used instead of LMP?
Yes. If conception date is known, add 266 days (38 weeks) to find the estimated due date.
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EverydayFeatures & Highlights
- Estimated Due Date & Trimester Milestones