Pregnancy Due Date Calculator
Estimate your baby's due date and track gestational age.
Pregnancy Due Date Calculator
Usually 28 days.
Pregnancy Due Date & Conception Calculator
Knowing your Estimated Due Date (EDD) is the most exciting and essential first step of early pregnancy. It helps your obstetrician schedule crucial clinical milestones such as ultrasound scans, blood tests, and prenatal care visits. The Calculay Pregnancy Calculator provides a highly accurate, scientifically backed estimation of your gestational age and the date your baby is expected to be born.
How is Your Due Date Calculated?
In obstetrics, there are three primary methods used by doctors worldwide to estimate your EDD:
1. Last Menstrual Period (LMP) Method (Naegele's Rule)
This is the standard clinical method. Because pinpointing the exact day of ovulation or conception is difficult, doctors calculate pregnancy from the first day of your Last Normal Menstrual Period (LNMP).
- Formula: First day of LMP + 7 days - 3 months + 1 year
- Example: If your LMP started on January 1, 2024. Add 7 days = January 8. Subtract 3 months = October 8. Add 1 year = Expected due date is October 8, 2024.
2. Conception Date Method
If you know the exact day you conceived (such as through rigorous temperature tracking, ovulation testing, or an IUI procedure), this method is highly accurate.
- Formula: Date of Conception + 266 days (38 weeks).
3. IVF Transfer Date Method
For mothers undergoing In Vitro Fertilization (IVF), the precise age of the embryo is known at the time of transfer. You simply add 266 days and then subtract the age of the transferred embryo (either 3 days or 5 days) to get your due date.
Why Do Babies Rarely Arrive on Their Due Date?
It is a well-documented medical fact that only about 4-5% of babies are born precisely on their Estimated Due Date. A normal, full-term human pregnancy lasts anywhere between 38 and 42 weeks. The EDD generated by our Due Date Calculator is simply a statistical "target day" within a four-week window of when you will likely go into spontaneous labor. Always consult your gynecologist to confirm this date via an early dating ultrasound (typically performed around 8-10 weeks).