Track your pregnancy progress with due date, trimester, and fetal development info.
Pregnancy Calculator
Enter the first day of your last period
About the Pregnancy Calculator
The Pregnancy Calculator helps you track your pregnancy progress, calculate your due date, and understand which trimester and week of pregnancy you're in.
Enter your last menstrual period date or conception date to get detailed pregnancy information.
Use it for:
- Calculating your due date
- Tracking pregnancy weeks and trimesters
- Understanding fetal development milestones
- Planning for your baby's arrival
Pregnancy Timeline:
- First Trimester: Weeks 1-13 (months 1-3)
- Second Trimester: Weeks 14-27 (months 4-6)
- Third Trimester: Weeks 28-40+ (months 7-9+)
Due Date Calculation:
- From LMP: 280 days (40 weeks) from first day of last period
- From Conception: 266 days (38 weeks) from conception date
This calculator provides estimates. Always consult with your healthcare provider for medical advice and pregnancy monitoring.
Frequently Asked Questions
While the 280-day (40-week) rule is the medical standard, it's actually an estimate based on Naegele's Rule. In reality, only about 5% of babies arrive exactly on their due date. Most 'full-term' births happen anywhere between 37 and 42 weeks. We recommend using this date as a planning target rather than a fixed deadline.
If you know your exact conception date (common with IVF or tracking ovulation), your calculation will likely be more precise. However, because most people don't know the exact moment of conception, doctors use your Last Menstrual Period (LMP) as the universal starting point. Our tool allows you to toggle between both to see the difference.
Trimesters aren't perfectly equal. The first trimester (weeks 1-13) is about rapid development; the second (14-27) is often the 'honeymoon phase' where energy returns; and the third (28-40+) is focused on final growth. Our tracker highlights these milestones so you know what to expect physically in each stage.
Due date is calculated as 280 days (40 weeks) from the first day of your last menstrual period (LMP). This is the standard method used by healthcare providers.
If you know your conception date, the due date is 266 days (38 weeks) from conception. However, LMP-based calculation is more commonly used and is what most doctors use.
Only about 5% of babies are born exactly on their due date. Most babies are born between 37-42 weeks. The due date is an estimate, and your doctor will monitor your pregnancy progress.
Medical Disclaimer: This calculator provides estimates and general information only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult with your healthcare provider for personalized pregnancy care and monitoring.