The calculator allows the user to add or subtract a specified time interval in days, hours, minutes, and seconds to a specified date and return two dates: the date plus the interval and the date minus the interval.

Calculator sums up input time intervals

This calculator allows users to enter time in various units such as days, hours, minutes and seconds in any combination and then normalizes the value into days, hours, minutes and seconds. The calculator also displays the entered time in other units such as hours plus minutes plus seconds, minutes plus seconds, and seconds only.

Calculate time interval between two dates

This article describes how to use a masked input in your calculators