Time Duration Calculator
Add, subtract and convert hours, minutes and seconds.
Enter your values
Results update instantly as you type — no submit needed.
Results
- Result
- 4:05:45
- Decimal hours
- 4.0958
- Total minutes
- 245.75
- Total seconds
- 14,745
Quick answer
Convert both durations to seconds, add or subtract, then convert back to hours, minutes and seconds.
How to use the Time Duration Calculator
- 1Enter the first duration as HH:MM:SS.
- 2Enter the second duration.
- 3Choose add or subtract.
Frequently asked questions
Why is 1:30 not 1.30 hours?
Minutes are sixtieths, so 1:30 is 1.5 decimal hours. Payroll and billing always use the decimal form.
Can I enter durations over 24 hours?
Yes — the hours field is not capped, so 36:00:00 is valid.