DayOfWeekdate - any calendar dateImportant To avoid errors when using dates, always use four-digit years. For more information about how FileMaker Pro handles two-digit dates, see Conversion of dates with two-digit years.DayOfWeek(“10/8/2014”) returns 4.DayOfWeek(Date(10;9;2014)) returns 5.DayOfWeek(ProjectDue) returns 3 when the date in ProjectDue is 10/7/2014.