Calculate duration

Add or subtract elapsed times expressed as seconds or hours, minutes, and seconds.

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ToolDuration Calculator
Input
Output
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Preview

How it works

Each operand becomes a scalar second count before addition or subtraction. The signed result is then decomposed into days of exactly 86,400 seconds, hours, minutes, and seconds.

  • Addition is the initial operation.
  • These are exact elapsed durations, not local calendar periods that may cross daylight-saving changes.

Worked example

Add Two Durations
Add a 2-hour meeting and a 45-minute session
Input
											Input1: 02:00:00
Input2: 00:45:00
Output
												02:00:00 + 00:45:00 = 02:45:00

Result: 02:45:00
Total seconds: 9900

When to use this

Media edits total clip running times, training logs subtract split timestamps, and service-level reports combine processing durations.

Edge cases

  • 25:00:00 is treated as 90,000 elapsed seconds rather than rejected as an invalid time of day.
  • Subtracting a larger operand produces a signed duration instead of wrapping around midnight.
  • Fractional seconds are rounded in the scalar result while the displayed components use whole seconds.

References