Time Difference Calculator
Enter a start time and an end time to calculate the exact duration between them — including shifts that run past midnight into the next day.
Duration
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Enter both times to calculate.
How the Time Difference formula works
Duration in minutes, converted to hours and minutes:
Duration (minutes) = End time − Start time (add 24 hours if the end time is earlier, i.e. crosses midnight) Hours = floor(Duration / 60) Minutes = Duration mod 60
Step-by-step calculation
- Convert both the start and end times to minutes since midnight.
- Subtract the start from the end.
- If the result is negative, add 24 hours (1,440 minutes) to account for crossing midnight.
- Convert the total minutes back into whole hours and remaining minutes.
Worked example
A shift from 10:30 PM to 6:15 AM: since the end time is earlier in the clock, it crosses midnight. Duration = (6:15 + 24:00) − 22:30 = 7 hours 45 minutes.
Frequently asked questions
How do I calculate a shift that crosses midnight?
Just enter the start and end times as shown on the clock — the calculator automatically detects when the end time is earlier than the start time and adds a full day to account for the overnight crossing.
How is this different from the Time Card Calculator?
This calculator finds the duration between a single start and end time. The Time Card Calculator sums multiple days of hours (already totaled) across a week, including overtime pay calculations.