Estimate a due date and surrounding window from the last period.
Preparing calculator…
A due date is an estimate, not a prediction of the delivery day. Early ultrasound and clinical information can revise it.
Not a diagnosisFor general health education and estimation only. It does not diagnose a condition and is not treatment, medication, diet or training advice.
first day of LMP + 280 daysA preliminary estimate when the first day of the last menstrual period is known and cycles are near 28 days.
Irregular cycles, uncertain dates, assisted reproduction, recent birth or recent hormonal contraception require clinical dating.
Input accuracy, measurement technique, rounding and individual variation all affect the result. Internal precision is retained and only displayed values are rounded.
Contact prenatal care after a positive test. Severe pain, heavy bleeding, fainting or other urgent symptoms require immediate care.