Time Duration Calculator

About this calculator

This calculator finds the elapsed time between a start and end clock time, handling the awkward parts automatically: it correctly carries over the hour when minutes go negative, and it accounts for the case where the end time is on the following day (like an overnight shift). The result is given three ways — hours and minutes, total minutes, and decimal hours — because different situations call for different formats.

It's used constantly for payroll and timesheets, where hourly wages need to be multiplied by decimal hours rather than a clock-style duration; by shift workers checking how long a night shift actually runs; and by anyone timing an activity, meeting or commute where doing the subtraction by hand risks an off-by-one-hour mistake around the top of the hour.