Find elapsed time and time after a break
Choose a 12-hour or 24-hour clock, enter the start and end times, and select Calculate. In 12-hour mode, choose AM or PM for each time: 12 AM is midnight, and 12 PM is noon. Changing the clock format clears both time fields.
For an overnight interval, select End time is on the next day. Select this yourself when the end time is earlier than the start time. Enter a break in whole minutes, or leave it blank for no break. The result includes elapsed time, time after the break, total minutes and decimal hours after the break.
Try example fills the form without calculating. Reset clears the quantities.
Method and overnight example
Each clock time becomes a minute count: hours × 60 + minutes. Elapsed minutes are end − start, with 1,440 minutes added only when next day is selected. Time after the break is elapsed − break, and decimal hours are minutes after break ÷ 60.
The calculation uses 60 minutes per hour and 24 hours per day, as listed in NIST’s time-unit conversion table.
From 22:30 to 06:15 the next day, elapsed time is 7 hours 45 minutes. With a 30-minute break, the remaining duration is 7 hours 15 minutes, or 7.25 decimal hours.
Equal times, limits and precision
Equal clock times give 0 hours on the same day or 24 hours with next day selected. The supported interval is 0–24 hours. A later end time with next day selected would exceed 24 hours and is rejected. A break cannot exceed elapsed time.
Inputs use whole minutes; seconds are not accepted. Decimal hours are shown to at most four decimal places. For example, one minute is displayed as 0.0167 hours; that decimal is rounded, while the minute count remains exact.
This is a clock-only calculation. It does not use calendar dates, time zones, daylight-saving changes, leap seconds or payroll rounding rules. For an actual dated interval across a clock change, the displayed wall-clock difference may differ from elapsed time. To convert a duration longer than a day, use the Decimal Hours Calculator.