Due Date Calculator

Name: Due Date Calculator
Rating: 4.9 (1456 reviews)

Calculate estimated due date using Last Menstrual Period or conception date.

Calculator

Calculate From

Date

Cycle Length (LMP only)

Result

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Naegele's rule: Due date = LMP + 280 days (40 weeks). About 80% of babies are born within 2 weeks of estimated due date. Only 5% are born exactly on the due date. Always confirm via ultrasound with your OB-GYN.