Pregnancy Due Date Calculator

Expected Date of Delivery (EDD)

Calculation of the pregnancy due date or the expected date of delivery (EDD) of your baby is possible by using this unique pregnancy due date calculator. Just enter the 1st day of your last menstrual period below and you can find the expected date of delivery or your due date.

Pregnancy, on average, lasts 267 days (38 weeks) from conception. If you positively know your conception date, you can add 267 days to it for your due date. A simple formula for calculation of your due date is also provided after this pregnancy due date calculator.

Calculating Your Due Date

Every month in a human female's ovary, a mature ovarian follicle ruptures and discharges an ovum. This process is called ovulation. Ovum is the female gamete or the cell responsible for reproduction. When an ovum fuses with a sperm, the process is called fertilization and when this fertilized ovum implants itself in the uterus, it is called conception.The few days around the time of ovulation are the fertile period.

A female can conceive only during those few days because the ovum is discharged between the middle of the two menstrual cycles (approximately 14 days after the first day of your last menses) and survives just for 2-3 days without fertilization. So considering the life span of a sperm and the ovum, the fertile period is calculated using the ovulation time. A female is considered fertile 2 to 3 days before and after ovulation.

Ovulation calendars and ovulation calculator are commonly used to identify the most fertile period for conception and plan physical relationships. But an ovulation calculator is only useful if your periods are regular. If your periods are irregular then it is not possible to predict the ovulation date. In such cases you can use other methods to identify ovulation time like measuring basal body temperature in morning, checking the consistency of vaginal mucous, using an LH strip or going in for an ovulation study (usually done as successive trans-vaginal ultrasonography).

If your periods are regular, you can use the ovulation calculator below to identify your ovulation time and predict your most fertile period.

Use our due date calculator to work out when you might expect your baby to arrive. This will give you a rough idea. As part of your antenatal care, your midwife or doctor will also offer you a dating scan that will give you a more accurate due date for the birth of your baby.

Due Date Calculator

Pregnancy, on average, lasts 267 days (38 weeks) from conception. If you positively know your conception date, you can add 267 calendar days to it to calculate your pregnancy due date.

The following formulas can also tell your Expected Due Date :

Date of the first day of your last period + 281 days=due date

or

Date of the first day of your last period + 7 days - 3 months=due date

The due date calculation methods here are based on the average 28-day cycle.

If you don't like arithmatic calculation, you can just use our Due Date Calculator above.