calculator
Time Duration Calculator
Use the time duration calculator to find elapsed hours, work hours, shift length, study sessions, and overnight time ranges from HH:MM inputs.
Calculate elapsed time for work shifts, study blocks, travel windows, overnight schedules, project logs, and simple time-card checks.
Result
How it works
Enter start and end times in 24-hour HH:MM format. The calculator converts both times to minutes, optionally treats the end time as the next day, subtracts break minutes, and shows the result as minutes, hours plus minutes, and decimal hours.
Examples
Work shift
Input: 09:15 to 17:45 with 30 break minutes
Output: 8 hours, 480 total minutes
Short meeting
Input: 10:00 to 10:45
Output: 45 minutes, 0.75 decimal hours
Study block
Input: 19:10 to 21:40 with 10 break minutes
Output: 2 hours 20 minutes
Overnight shift
Input: 22:30 to 01:15 overnight with 15 break minutes
Output: 2 hours 30 minutes
Travel window
Input: 06:05 to 08:50
Output: 2 hours 45 minutes
Lunch break
Input: 08:00 to 16:30 with 60 break minutes
Output: 7 hours 30 minutes
Project log
Input: 13:25 to 15:05
Output: 1 hour 40 minutes
FAQ
What time format should I enter?
Use 24-hour HH:MM format, such as 09:00, 17:30, or 22:15.
Can the calculator handle overnight times?
Yes. Choose overnight mode when the end time is on the next calendar day.
What happens if the end time is earlier than the start time?
Same-day mode returns a validation error. Overnight mode treats the end time as the next day.
How are break minutes handled?
Break minutes are subtracted from the gross duration. Break minutes must be zero or greater and less than the total duration.
Does this calculate payroll?
No. It calculates elapsed time only. Payroll, overtime, rounding, labor rules, and local compliance policies should be checked with the responsible source.
Does it include dates or time zones?
No. The MVP uses time-of-day inputs only and does not include dates, time zones, daylight-saving changes, or business rules.
Why show decimal hours?
Decimal hours are useful for time sheets, invoices, and planning notes when a system expects values like 2.5 hours.
Can I use it for meetings or study sessions?
Yes. It is useful for everyday elapsed-time checks as long as you do not need official payroll or compliance logic.