Health & Fitness Calculators
Pregnancy Calculator
Track your due date and pregnancy week.
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About the Pregnancy Calculator
Enter the first day of your last menstrual period and the calculator estimates your due date (40 weeks later), how many weeks and days along you are, your trimester, and the estimated conception date. It's the quick way to track a pregnancy's timeline — your provider's dating scan remains the authoritative source.
How to use the Pregnancy Calculator
- 01Enter your first day of your last period.
- 02Read the result instantly — it recalculates as you type.
- 03Adjust the numbers to model different scenarios.
Frequently asked questions
How is the due date calculated?
By adding 280 days (40 weeks) to the first day of your last menstrual period — the standard Naegele's rule estimate.
How accurate is it?
It's a solid estimate, but only about 5% of babies arrive exactly on the due date. An ultrasound refines the dating.