Pregnancy Due Date Calculator

Calculate your estimated due date based on your last menstrual period (LMP). Track your pregnancy week and trimester.

First Day of Last Menstrual Period (LMP)

Frequently Asked Questions

How is the due date calculated?

The due date is calculated by adding 280 days (40 weeks) to the first day of your last menstrual period (LMP). This is known as Naegele's Rule.

How accurate is the due date?

Only about 5% of babies are born on their exact due date. Most babies arrive within 1-2 weeks before or after the estimated date.