Time Duration Calculator
Add and subtract multiple time durations in hours, minutes, and seconds. Free time calculator for timesheets, video editing, and project tracking.
About Time Duration Calculator
Add and subtract multiple time durations with ease. Enter hours, minutes, and seconds for each entry, toggle between addition and subtraction, and see the running total in real time. Results are shown in HH:MM:SS format as well as decimal hours, total minutes, and total seconds. Perfect for timesheet calculations, project tracking, and billing.
How to Use Time Duration Calculator
Enter your values
Open Time Duration Calculator and enter the values you want to calculate or convert.
Select units or options
Choose the input and output units, formats, or calculation parameters.
View results instantly
Results are calculated in real-time as you type — no submit button needed.
Copy or use the result
Copy the calculated result or use it directly in your work.
Frequently Asked Questions
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