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Pregnancy Calculator: Find Your Due Date

Your Results

Due Date
Thursday, February 26, 2026
Current Week
Week 0
Trimester
First Trimester

Important Dates

First Trimester Ends
8/21/2025
Second Trimester Ends
11/20/2025
Third Trimester Ends
2/26/2026

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Understanding Pregnancy Calculation

Calculating your due date is an important first step in your pregnancy journey. While only about 5% of babies are born on their exact due date, knowing your estimated due date helps you and your healthcare provider monitor your pregnancy's progress.

How is the Due Date Calculated?

The calculator uses Naegele's rule, which adds 280 days (40 weeks) to the first day of your last menstrual period. For conception date calculations, it adds 266 days (38 weeks) to the conception date.

Pregnancy Trimesters

First Trimester

Weeks 1-13: Early pregnancy symptoms, rapid development of major organs and structures.

Second Trimester

Weeks 14-27: Often called the "golden period" with reduced morning sickness and increased energy.

Third Trimester

Weeks 28-40: Final growth and development, preparation for birth.

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. This method, known as Naegele's rule, is the standard way to estimate your due date.

How accurate is the pregnancy calculator?

The calculator provides an estimate based on standard pregnancy duration. Only about 5% of babies are born on their exact due date, with most births occurring within two weeks before or after.