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Add or subtract time values in hours, minutes, and seconds. Convert results between decimal hours, total minutes, and total seconds.
A time duration calculator adds or subtracts time values (hours, minutes, seconds) and converts the result between multiple time units.
02:15:30
2.2583 decimal hours
| From | To | Multiply by |
|---|---|---|
| Hours | Minutes | × 60 |
| Hours | Seconds | × 3,600 |
| Minutes | Seconds | × 60 |
| Minutes | Dec. Hours | ÷ 60 |
| Seconds | Dec. Hours | ÷ 3,600 |
Formula
Result = Time₁ ± Time₂ (converted to total seconds)Time₁ = first time value in hours, minutes, and seconds
Time₂ = second time value in hours, minutes, and seconds
Worked Example
Adding two work shifts
Did you know? The 60-based time system (sexagesimal) originated with the ancient Sumerians around 2000 BCE. They chose base-60 because it has many divisors (1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, 60), making fractions easier to work with.
Sources
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