Time Duration Calculator
Calculate the hours and minutes between two times, or add and subtract a duration. Decimal hours for timesheets included.
How the time duration is calculated
Both modes work entirely in total minutes, then convert that figure back into hours, minutes and decimal hours so the result stays accurate even across midnight.
Common uses for a time calculator
Work out hours worked between clock-in and clock-out, then read the decimal hours for payroll and hourly pay.
Calculate the length of a shift that runs past midnight, such as 10:00 PM to 6:00 AM.
Add or subtract a duration from a time to find when a meeting, cooking timer or appointment will finish.
Frequently asked questions
How do I find the hours between two times?
Use the "Time between two times" tab, enter a start time and an end time, and the calculator instantly shows the duration as hours and minutes, total minutes, and decimal hours.
How does the calculator handle overnight times?
If the end time is earlier than the start time (for example 22:00 to 06:00), tick the "next day" toggle. The calculator then adds a full day so the overnight duration is counted correctly.
What are decimal hours and why do timesheets use them?
Decimal hours express minutes as a fraction of an hour: 30 minutes is 0.5, 15 minutes is 0.25. Payroll systems multiply decimal hours by an hourly rate, so 2h 30m worked at a fixed rate becomes 2.5 hours.
Can I add or subtract hours and minutes from a time?
Yes. Switch to the "Add / subtract time" tab, enter a base time, choose add or subtract, then type the hours and minutes. The result shows the new time in both 24-hour and 12-hour format, plus any day offset.
Do I enter times in 24-hour or 12-hour format?
The time fields use your device's native time picker, which may show AM/PM or 24-hour depending on your settings. Either way the underlying calculation is the same and fully accurate.