Pregnancy Due Date Calculator
Calculate your due date and track pregnancy milestones from your LMP
About Pregnancy Due Date Calculator
Enter your last period date to calculate your due date, current week, and trimester. See a complete milestone timeline for your entire pregnancy journey.
- Calculates due date using Naegele's rule
- Shows current week, trimester, and days remaining
- Complete milestone timeline for all 40 weeks
- Highlights key developmental events by trimester
- Calculates from last menstrual period date
Everything runs in your browser — your data never leaves your device.
How to Use Pregnancy Due Date Calculator
- Enter the date of your last menstrual period (LMP)
- Click Calculate Due Date
- View your estimated due date, current progress, and milestone timeline
Frequently Asked Questions
How is the due date calculated?
The estimated due date is calculated by adding 280 days (40 weeks) to the first day of your last menstrual period (LMP). This is called Naegele's rule.
How accurate is the due date?
Only about 5% of babies are born on their exact due date. Most births occur within two weeks before or after the estimated date. An ultrasound in the first trimester can provide a more precise estimate.
What are the three trimesters?
First trimester: weeks 1-12. Second trimester: weeks 13-26. Third trimester: weeks 27-40. Each trimester has distinct developmental milestones.
