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Time Duration Calculator

Add or subtract hours, minutes, and seconds across multiple entries.

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Total
00:00:00
0.00 decimal hours · 0 total minutes

About This Tool

Free time duration calculator online — add or subtract two time durations (in hours, minutes, and seconds), or add multiple duration entries together to get a total. Enter durations like "2h 30m" and "1h 45m" and instantly see the sum or difference in a clean HH:MM:SS format, along with the total in decimal hours and total minutes. Useful for totaling work hours from multiple time entries, calculating overtime, adding up video or audio clip lengths, estimating combined task durations for project planning, and payroll time-sheet calculations. All math runs instantly in your browser as you edit any value.

How to Use

  1. 1

    Enter your time durations

    Type each duration as hours, minutes, and seconds — add more rows as needed.

  2. 2

    Choose add or subtract

    Select whether to sum all durations or subtract one from another.

  3. 3

    Read the total

    See the result in HH:MM:SS format, plus total minutes and decimal hours.

Frequently Asked Questions

How do I add up multiple work shifts?+
Add a row for each shift duration (e.g., 8h 15m, 7h 45m) and the calculator sums them into a single total shown in HH:MM:SS and decimal hours — handy for payroll.
What is decimal hours and why does it matter?+
Decimal hours express minutes as a fraction of an hour (e.g., 30 minutes = 0.5 hours). Many payroll and invoicing systems require decimal hours instead of HH:MM format.

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