Time Duration Adder & Interval Sum Calculator
Need to sum the lengths of 10 video clips, calculate total employee work hours, or sum podcast episode durations? Enter multiple time intervals and get instant combined totals.
How to Use Time Duration Adder & Calculator
Add Time Entries
Enter durations in HH:MM:SS or MM:SS format into row inputs.
Add or Remove Rows
Use the + Row button to add as many time segments as needed.
Read Combined Total
Review total sum formatted as Days, Hours, Minutes, and Seconds or total seconds.
About Time Duration Adder & Calculator
Converts all entered durations into base seconds, sums the total, and performs modular division to output days (86400s), hours (3600s), minutes (60s), and residual seconds.
Supported Formats
Operational Limits
- •Calculations sum non-negative time intervals.
Key Features
- Add unlimited rows of time duration entries
- Automatic carry-over from seconds to minutes, minutes to hours, and hours to days
- Shows total in standard HH:MM:SS, decimal hours, and total minutes/seconds
- Average duration per entry calculation
- One-click copy and reset
Frequently Asked Questions
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