Time Duration Calculator
Add and subtract signed clock durations and view total seconds, minutes and decimal hours.
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How to use this tool
- Enter signed H:MM:SS or MM:SS durations, one per line.
- Calculate the sum; durations may exceed 24 hours.
Things to know
- Minutes and seconds within a clock value must be from 00 to 59. Calendar months and daylight-saving changes are not durations.
- At most 10,000 duration lines; each is at most 10^12 seconds. The combined duration must remain a safe whole-second integer.
- Use no more than 200,000 characters across the input and settings.
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