Date and Time Guide
Time Duration Calculator Guide: Hours and Minutes Between Times
Calculate elapsed time between two clock times, including spans that cross midnight.
Quick answer
A time duration calculator finds the elapsed hours and minutes between a start time and an end time. If the end time is earlier than the start time, the calculator can treat it as crossing midnight. For example, 22:45 to 01:15 is 2 hours and 30 minutes.
Why this matters
Time math is easy to get wrong because clocks reset at midnight and hours use base 60, not base 100. A difference of 1.30 on a calculator screen does not automatically mean 1 hour 30 minutes unless you converted the minutes correctly.
Example
A shift starts at 9:20 and ends at 17:05. From 9:20 to 17:20 is 8 hours, then subtract 15 minutes, so the duration is 7 hours 45 minutes. In total minutes, that is 465. This is often more useful for payroll or scheduling systems.
How to use the calculator
Enter start and end times in 24-hour format. Use total minutes if you need to multiply by a rate or compare multiple sessions. If a duration spans several days, combine this with the date difference calculator.
Common mistakes
One mistake is reading 7 hours 45 minutes as 7.45 hours. In decimal hours, 45 minutes is 0.75, so the value is 7.75 hours. Another mistake is forgetting unpaid breaks. The calculator gives elapsed clock time, not necessarily billable or paid time.
When not to rely on this estimate
For payroll, overtime, contracts, or compliance tracking, follow the official timekeeping rules. Rounding, breaks, local labor rules, and time zones may change the final reported duration.
FAQ
Can it cross midnight?
Yes, an earlier end time is treated as the next day.
Are breaks included?
Only if you subtract them yourself.