👶 Pregnancy Due Date Calculator

Estimate your due date based on your last menstrual period or conception date.

⚠️ Health Disclaimer: Due date estimates are approximate. Only about 5% of babies are born on their exact due date. This calculator is for informational purposes only. Always consult your healthcare provider for pregnancy care.

Calculation Method

First Day of Last Menstrual Period

Estimated Conception Date

Estimated Due Date

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Current Week

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How the Due Date Is Calculated

The standard due date calculation uses Naegele's Rule: add 280 days (40 weeks) to the first day of your last menstrual period. This assumes a regular 28-day cycle. If you know your conception date, add 266 days (38 weeks) instead.

Only about 4-5% of babies arrive on their exact due date. A full-term pregnancy is considered 37 to 42 weeks. Your healthcare provider may adjust the due date based on early ultrasound measurements.

Reference: ACOG - How Your Due Date Is Calculated