Reverse Due Date Calculator

Wondering when your baby was conceived? You can calculate your pregnancy conception date with this handy tool. With just a click, you can find out when your baby was conceived with the babyMed conception calculator and reverse pregnancy due date calculator. Just input your baby's birthday and click!

Calculating an accurate due date is an important first step in pregnancy. The calculation of the estimated due date (EDD) is based on the day of the date of ovulation and fertilization. The EDD can be calculated by adding 266 days to the day of ovulation/fertilization. The first step is to know the first day of your last menstrual period and the length of your menstrual cycle. Then, just enter the date of the first day of the last menstrual period and your average cycle length.

Alternatively, you can also enter the day of ovulation, the weeks and days of the pregnancy on ultrasound, or the IVF egg or embryo transfer date. If you don't know the exact date of ovulation, then use our ovulation calculator to the approximate first day of your last menstrual period in a 28-day cycle. If your cycles are longer or shorter than 28 days, then the day of ovulation may change. Don’t worry because this calculator takes that into consideration when calculating your estimated due date. The conception calculator will give you an estimated date of the probable time when conception occurred. If you’re pregnant and want to see if you're estimated due date aligns with what your doctor said, don't forget to try our pregnancy due date calculator!