Pregnancy Week Calculator
Track your pregnancy progress and calculate your due date. Find out how far along you are and what developmental milestones to expect.
This is used to calculate gestational age
Enter your last period date to see your pregnancy progress.
How It Works
Pregnancy is typically dated from the first day of your last menstrual period (LMP), even though conception occurs about 2 weeks later. A full-term pregnancy is 40 weeks (280 days) from LMP, divided into three trimesters.
Your healthcare provider may adjust your due date based on ultrasound measurements, especially in the first trimester when dating is most accurate.
Frequently Asked Questions
How accurate is my due date?
Only about 5% of babies are born on their due date. Most births occur within two weeks before or after. Your due date is an estimate, and babies arrive when they're ready.
When are the trimesters?
First trimester: Weeks 1-12. Second trimester: Weeks 13-26. Third trimester: Weeks 27-40. Each trimester brings different developments and symptoms.
What's considered full term?
Early term: 37-38 weeks. Full term: 39-40 weeks. Late term: 41 weeks. Post-term: 42+ weeks. Babies born at full term generally have the best outcomes.
Why count from my last period?
Dating from LMP is a standard convention because most women know when their period started but not exactly when they ovulated or conceived. This means you're "2 weeks pregnant" at conception.