⏱️ Time Duration Calculator
Add or subtract two time durations — hours, minutes, and seconds — and get the exact total. Useful for stacking meeting lengths, workout splits, cooking times, or video/audio clip durations.
How the Time Duration Calculator works
Both durations are converted to total seconds, added or subtracted, then converted back into a clean hours:minutes:seconds display, correctly carrying over between units.
Step-by-step calculation
- 1Enter the first duration (h:m:s).
- 2Enter the second duration and choose add or subtract.
- 3Everything is converted to seconds and back.
Worked example
2:45:30 + 1:30:45 = 4:16:15 (3 hours 75 minutes 75 seconds carried over).
Time Duration Calculator examples
| Hours | Result |
|---|---|
| 1 | 3h 15m 0s |
| 2 | 4h 15m 0s |
| 3 | 5h 15m 0s |
Other inputs kept at the calculator's default values. Results calculated by this calculator.
Why use a Time Duration Calculator?
Add up workout times, video lengths, flights or work sessions.
Important factors that can affect your results
- Carrying minutes and seconds over 60.
- Negative results when subtracting a larger time.
- Typing minutes in the hours box.
Frequently asked questions
Can I subtract a duration instead of adding?
Yes — switch the operation to subtract; the result won't go below zero.
Does it handle durations longer than 24 hours?
Yes — durations aren't capped at 24 hours, so totals can run into multiple days worth of hours.
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Last reviewed November 2026 · How we build and check our tools · Report a problem