Hours and Minutes Calculator
Add or subtract hours and minutes, carrying minutes into hours correctly, and see the result in decimal hours for timesheets and pay.
Your results
Calculation breakdown
- Total
- (h1×60+m1) ± (h2×60+m2), converted back to hours and minutes
- Decimal hours
- Total minutes ÷ 60
Worked example
Adding 3h 45m and 2h 30m gives a total of 6h 15m, which is 6.25 decimal hours. Subtracting 2h 30m from 3h 45m leaves 1h 15m.
Assumptions
- Each duration uses whole hours and minutes from 0 to 59; seconds are not modelled.
- If the second duration is longer when subtracting, the difference is shown as a negative value.
How this calculator works
This calculator adds or subtracts two durations expressed in hours and minutes and returns the combined result, correctly carrying minutes over into hours. It's useful for totalling up multiple work shifts, tasks or activities logged separately.
Add or subtract hours and minutes correctly
Time does not add like ordinary decimals because an hour has 60 minutes, not 100. The calculator converts each duration to minutes, adds or subtracts them and converts the answer back, so 3h 45m plus 2h 30m is 6h 15m rather than 5h 75m.
The result is also shown in decimal hours and total minutes. When subtracting, a longer second duration produces a negative difference with a note, which helps when checking how far a timesheet is over or under its target.
Totalling several shifts or tasks
To total a week of shifts, add the first two, then feed the running total back in as the first duration and add the next shift. Use the decimal-hours figure when a payroll form or invoice asks for hours as a single number.
Check how your employer rounds start and finish times before relying on a total for pay. Some workplaces record time to the minute, while others round to set increments under an award, agreement or internal policy.
Frequently asked questions
Can I subtract one duration from another?
Yes, choose the subtract operation. If the second duration is longer, the difference is shown as a negative value with a note.
What happens if minutes add up to more than 60?
The calculator automatically carries the extra minutes over into whole hours.
Can I use this for adding up several shifts?
Yes, run it repeatedly, feeding each running total back in as one of the two durations.
Content responsibility
Maintained by CalcAussie and last updated 15 October 2026. Checks applied: calculation method, worked examples, Australian terminology, material assumptions, official references where an external rule applies, and user-facing limitations.
Calculator results remain estimates based on the figures entered. Check material decisions against current official information and report a suspected error so it can be reproduced and corrected.