How do I calculate a time range that crosses midnight?
Leave Treat an earlier end time as the next day selected when the range crosses midnight. Clear it only when you intentionally want the same-day subtraction shown as a negative duration.
Find the duration between two clock times, or add and subtract a precise amount of time. Overnight ranges and day rollover are reported clearly.
The calculator works in whole seconds and keeps the day offset separate from the displayed 24-hour clock time, so a result that crosses midnight is never hidden.
Enter two 24-hour clock times to get the elapsed hours, minutes, and seconds. When an end time is earlier than the start, the overnight option treats it as a time on the following day.
Add or subtract any non-negative number of hours, minutes, and seconds. The displayed clock result wraps to a 24-hour day while a separate day offset preserves the complete answer.
Leave Treat an earlier end time as the next day selected when the range crosses midnight. Clear it only when you intentionally want the same-day subtraction shown as a negative duration.
Time duration subtracts one clock time from another. Add or subtract starts with one clock time and applies a separate number of hours, minutes, and seconds.
The clock result wraps within 24 hours, while Day rollover reports how many days forward or backward the full calculation moved. This keeps additions such as 30 hours from looking like a simple 6-hour result.
No. This tool performs clock arithmetic only. It does not use calendar dates, time zones, daylight saving changes, work schedules, or automatic break deductions.
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