Time duration · date and clock
Time duration · date and clock: use start date, start time, end date. Review the formula, worked example and calculation steps.
Inputs
Use the units shown—
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Formula & explanation
Hours = 24 × calendar day difference + (end minutes−start minutes)/60
Variables & units
- Start date
- Gregorian date
- Start time
- 24-hour time
- End date
- Gregorian date
- End time
- 24-hour time
Worked example
2026-01-01 09:00 to 2026-01-02 17:00 is 32 hours.
Assumptions
Naive civil-time arithmetic without daylight saving; negative results indicate reversed endpoints.
Formula version 1.0.0. JavaScript floating-point arithmetic applies. Results display up to 6 decimal places; stored values retain available precision. Use the units shown.
Practice with an example
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