About this Time Duration
Calculating the difference between two times is confusing because time isn't base-10 (there are 60 minutes in an hour, not 100). This calculator finds the exact duration in hours and minutes between any start and end time.
Who this calculator is for
- Anyone measuring elapsed time between two clock times for work, travel, study, or daily planning.
- Users who need a clean hour-minute duration before converting it to decimal time.
- People checking overnight spans without having to do manual 24-hour math.
When to use it
- Work out how long a shift, meeting, trip, or activity lasted between two times.
- Measure elapsed time before applying break deductions or payroll conversions elsewhere.
- Quickly convert a start/end pair into total minutes for scheduling decisions.
How to use this calculator
- Select the Start Time.
- Select the End Time.
- The result shows the Duration (e.g., 8h 30m) and the Total Minutes.
Key assumptions
- If the end time is earlier than the start time, the calculator assumes the span crossed midnight once.
- The result reflects a single 24-hour cycle and is not intended for multi-day durations.
- Breaks are not deducted here; this tool measures raw elapsed time only.
Accuracy and testing
Review formula sources, default test cases, assumptions, unit handling, rounding rules, and changelog for this calculator.
How this calculator works
1. Convert both times to minutes from midnight.
2. Subtract Start from End.
3. If End < Start, assume the time crossed midnight and add 24 hours (1440 minutes).
4. Convert the result back to Hours and Minutes.
Inputs explained
Start/End Time
The clock time. The calculator handles the 24-hour format logic automatically.
Understanding your results
The output is the length of time elapsed. Decimal Hours is useful for payroll (e.g., 8.5 hours).
Example scenarios
Work Day
Start 9:00, End 17:30. Duration: 8h 30m (8.5 hours).
Overnight Shift
Start 22:00, End 06:00. Duration: 8h 0m.
Key Features
- Overnight Calculation
- Decimal Conversion
- Simple Interface
Tips & Best Practices
- If the times span more than 24 hours, this basic calculator assumes the closest duration within a 24-hour window.
- Useful for timesheets, flight durations, and cooking.
Glossary of Terms
- Elapsed Time
- The amount of time that passes from the start of an event to its end.
- Decimal Hours
- Time expressed as a decimal number (e.g., 1 hour 30 minutes = 1.5 hours).