Base-60 arithmetic, handled for you
Add or subtract durations in hours and minutes without decimal confusion. Because 1.5 hours is 1:30, not 1:50.
Time is the one everyday unit that is not decimal. Sixty minutes to the hour means 45 + 45 gives 1:30, not 90-something, and mental arithmetic goes wrong fast.
This handles carrying across the hour boundary, which is where most manual timesheet errors come from.
What this calculator shows
- The total duration in hours and minutes
- Addition and subtraction of time spans
- Correct carrying when minutes pass 60
What to keep in mind
- Works with durations rather than clock times, so results can exceed 24 hours.
- Decimal hours and clock notation are different: 2.75 hours is 2:45.
FAQs
How do I convert decimal hours to minutes?
Multiply the fraction by 60. 0.25 hours is 15 minutes, 0.75 is 45. Payroll systems use decimals; clocks do not.
What is 1.5 hours in hours and minutes?
1 hour 30 minutes. Reading it as 1:50 is the classic mistake, and it inflates a timesheet by twenty minutes.
Can the total go past 24 hours?
Yes. These are durations, not clock readings, so 30:00 is a valid answer for a long project total.
Does it handle seconds?
It works in hours and minutes, which covers timesheets and scheduling. Second-level precision belongs to a stopwatch.
Worked example
Three tasks in an afternoon
Input: 1:45 + 2:30 + 0:50
Output: 5:05
Note: The minutes total 125, which carries as two hours and five minutes. Adding the columns separately is exactly where people slip.