Pregnancy Due Date Calculator

This pregnancy due date calculator will display the estimated due date date, conception, and other pregnancy events. Find out how many weeks you are on a certain date or on which date a certain week will be.

This estimate is based on the last menstrual period and the estimated date of conception. Your pregnancy due date calculator works by adding 40 weeks (280 days) to the approximate first day of your last menstrual period or 266 days to the day of ovulation.

Try our Reverse Due Date Calculator to find out when you became pregnant. There, you can enter your due date and we will calculate the exact days of conception. More importantly, we will provide the range of dates that you may have made love and got pregnant.

Please also look at the Interactive Pregnancy Wheel.

How To Use the Pregnancy Due Date Calculator

The first step is to know the first day of your last menstrual period and the length of your menstrual cycle. Enter the date of the first day of the last menstrual period and the 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.

The pregnancy due date calculator wil then calculate the exact date the baby will be due as well as other important events such as the date of implantation, when the baby will start moving and dates for important tests like amniocentesis, ultrasound, or glucose screen.

In addition to the Pregnancy Due Date Calculator, there is also a unique and handy offline tool called the Ovulation Calendar & 9-Month Pregnancy Wheel that helps determine a woman's ovulation date and serves as a traditional pregnancy wheel after conception has occurred.

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