Due Date Calculator

This calculator is to determine the milestones during your pregnancy. Your health care provider uses the number of weeks since your last menstrual period to describe how far along you are in your pregnancy. 

Enter the first day of your last menstrual period, then press 'Calculate.

  Month: Day: Year:

Calculated Result

Conception likely occurred around: (Approximately two weeks after your last menstrual period)
Period of greatest risk for birth defects: to Five to ten weeks gestational age (number of weeks since your last menstrual period)
Beginning of organ formation: Five Weeks Gestational Age
Major organs have formed: Ten Weeks Gestational Age
End of first trimester (12 weeks) - Risk of miscarriage decreases: 11 to 14 Weeks Gestational Age
Some preemies can now survive (23 weeks): 23 Weeks Gestational Age
End of second trimester
(27 weeks):
Estimated due date
(40 weeks - full term):
Window size: x
Viewport size: x