🤰 Pregnancy Due Date Calculator
Your estimated due date, current week, and key milestones.
The Due Date Calculator estimates your pregnancy due date and key milestones based on your last menstrual period (LMP) or conception date. Pregnancy typically lasts 40 weeks from the first day of your last period.
Frequently Asked Questions
How is a due date calculated?
The standard method (Naegele's rule) adds 280 days (40 weeks) to the first day of your last menstrual period. This assumes a 28-day cycle.
How accurate is the due date?
Only about 5% of babies are born on their exact due date. Most arrive within 2 weeks either side. It's an estimate, not a deadline.
What if my cycle is not 28 days?
If your cycle is shorter or longer, your actual due date may differ. An ultrasound scan is the most accurate way to confirm gestational age.
What are the pregnancy trimesters?
First trimester: weeks 1–12. Second trimester: weeks 13–26. Third trimester: weeks 27–40. Each has distinct developmental milestones.