All About Due Dates

Use the Due Date Calculator above to calculate your due date from your last menstrual period.  Select the month, day and year of your last menstrual period in the drop box controls in the middle of the calculator and click the "Set Your Last Period" button to calculate your due date.  Last menstrual period means the FIRST DAY of your last menstrual period, not the last day. 

The Due Date Calculator will not allow you to enter an invalid date for your due date. For example, if you try to enter "February 30, 2000," for the due date, it will be forced to a legal date, i.e., "February 29, 2000."

IMPORTANT:  Don't be surprized if the due date that you get from this Due Date Calculator is slightly different from the due date given to you by your care provider.  Your care provider more than likely used a "wheel" to calculate your due date. A wheel is a round, plastic or metal device that resembles an old-fashioned circular slide rule. These wheels are handed out free to care providers by drug companies. They can give inaccurate results in two ways:  They're cheaply made, therefore inherently inaccurate; and they don't account for leap years. If you have questions about your due date, direct them to your care provider.