Date and interval
Adds and subtracts a specified time interval to the specified date
Another "Date and time" calculator. Set the reference date and time interval as a number of days, hours, minutes and seconds (in any combination). The calculator displays the date with added and subtracted specified time interval.
Creation of this calculator was inspired by following inquiry : December 5 20.00.00 the end of the action. We know the time required to perform the action 58 hours 20 minutes 45 seconds. Calculator should calculate the starting date and time of action. Hope it will help somebody.