This conception calculator estimates probable conception dates from Birth, Last Menstrual Period and Due dates. These are probable conception dates based on an average 28 day cycle. To determine paternity for piece of mind or legal purposes, order a relationship test.

To use the calculator:

  1. Choose either the Due Date / Birth Date or the first Day of Last Menstrual Period
  2. Enter the date
  3. Click the 'Calculate' button.