Time duration calculator

Because the end time is earlier in the day than the start time and the next-day option is off, so the calculator is measuring backwards. For an overnight shift, tick "If the end is earlier, treat it as the next day" and the same two times return the positive interval.

No. This tool measures one continuous interval between two clock readings. To total a week of shifts with unpaid breaks taken out of each one, use the time card calculator, which has a break field per day and adds the days up for you.

They are not applied. The calculator treats both entries as plain clock readings and subtracts one from the other, so a night that contains a daylight saving change is an hour out. In spring that night is really an hour shorter than the clock suggests, and in autumn an hour longer.

The field follows your device: browsers on a system set to a 12-hour locale show an AM/PM control, and browsers on a 24-hour locale show 24-hour entry. Both produce the same underlying value. If you need to convert one written form to the other, the military time converter does exactly that.

The result is deliberately shown in hours and minutes so that 7 hr 45 min is never mistaken for 7.45 hours, a confusion worth about 18 minutes of pay per shift. When you do need the decimal form, for a timesheet or an invoice, the decimal time converter turns 7:45 into 7.75.