CALCULATORS
Duration Calculator
Add or subtract two durations entered as hours, minutes and seconds. Results are normalized and include total seconds.
Enter both durations to calculate the result.
Calculated in your browser. Your durations are not uploaded.
How to add or subtract durations
Enter each duration using whole hours, minutes and seconds. Choose whether to add the durations or subtract the second from the first. Minutes and seconds must be from 0 to 59; hours can be entered up to 999,999.
Duration calculation
Each input is converted to seconds, the selected operation is applied, and the result is converted back into days, hours, minutes and seconds as needed. A subtraction result can be negative when the second duration is longer than the first.
Examples
- 1 hour 45 minutes plus 30 minutes is 2 hours 15 minutes.
- 2 hours minus 3 hours is −1 hour.
- 90 seconds is normalized as 1 minute and 30 seconds.
Convert a time unit with the Time Converter, or compare calendar dates with the Date Calculator.