Obstetrics & Maternity
Pregnancy Calculator
Track your journey. Calculate the Estimated Due Date (EDD) and discover which gestational week you are in with the precision of Naegele's Rule.
Awaiting Data
Enter the date of your last period to generate your gestational schedule.
Your baby is due on
--/--/----
You are approximately at:
-- Weeks and -- Days
1st Tri
2nd Tri
3rd Tri
Estimated Dates
| End of 1st Trimester (13 wks) | -- |
| Fetal Viability (24 wks) | -- |
| End of 2nd Trimester (27 wks) | -- |
| Full Term (39 wks) | -- |
How is the Due Date Calculated?
Most pregnancies last about 40 weeks (or 280 days) from the first day of the last menstrual period. Our calculator uses Naegele's Rule, the worldwide standard adopted by obstetricians, but with an important difference: adjustment for your menstrual cycle.
Why adjust for the cycle?
The standard rule assumes a 28-day cycle with ovulation on the 14th day. If your cycle is shorter or longer, ovulation occurs at a different time, which alters the actual date of conception and, consequently, the due date.
Understanding Trimesters
- 1st Trimester (Week 1 to 13): Formation of the baby's vital organs. Adaptation period for the mother's body.
- 2nd Trimester (Week 14 to 27): Rapid growth phase. Generally the most comfortable phase for the pregnant woman. Gender reveal is possible.
- 3rd Trimester (Week 28 to 40+): Final maturation, baby weight gain, and preparation for birth.