Time Calculator
Add or subtract time durations in hours, minutes, and seconds. Instant result with no sign-up required.
Duration A
Duration B
Result
00:00:00
= 0 total seconds
How to Use the Time Calculator
- 1
Enter Duration A
Type hours, minutes, and seconds for the first time duration.
- 2
Select Operation
Click + to add the durations, or − to subtract Duration B from Duration A.
- 3
Enter Duration B
Type the second duration values.
- 4
Read the Result
The result shows instantly in HH:MM:SS format and also as total seconds.
About the Time Calculator
Adding and subtracting time durations is not straightforward with regular arithmetic because minutes and seconds use base-60 notation, not base-10. Carrying over 60 seconds into one minute (or 60 minutes into one hour) requires special handling that this calculator does automatically.
Common use cases include: calculating total project time from multiple task durations, determining the length of video content, figuring out flight layover times, and tracking billable hours for freelance work or payroll.
The calculator handles durations up to 999 hours and correctly wraps minutes and seconds that exceed 59 back into the next unit. Negative results (when subtracting a larger duration from a smaller one) are shown with a minus sign and a red result card.
All calculations are purely client-side. The result also shows the total in seconds, which is useful for feeding into other calculations or programming tasks.
You may also find our Hours Calculator and Date Difference Calculator helpful.
How to Use
- 1. Enter the first duration in hours, minutes, and seconds.
- 2. Enter the second duration.
- 3. Choose whether to add or subtract them, and read the result.
Frequently Asked Questions
Can I add more than two durations? expand_more
Currently two durations at a time. Chain the result into a new calculation for three or more.
What happens if minutes exceed 59? expand_more
The input is capped at 59. The carrying logic handles the result automatically.
Can the result be negative? expand_more
Yes — when subtracting a larger time from a smaller one, the result shows a negative duration in red.
Can I calculate across days? expand_more
Yes — hours can go up to 999, so 25 hours 30 minutes is valid.
Can I copy the result? expand_more
Select the displayed time and copy it. A one-click copy button may be added in a future update.
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