Date & Time
Time Duration Calculator
Last Updated: July 11, 2026
Calculate the exact time elapsed between two times or dates. Perfect for tracking work hours, travel duration, event timing, and more.
Duration Result
Hours : Minutes : Seconds
00:00:00
Total Hours (Decimal)
0.00 hrs
Total Minutes
0 min
How to Use This Time Duration Calculator
- Choose a mode: Select "Time Only" for same-day calculations or "Date & Time" for multi-day durations.
- Enter the start time using the time picker (hours, minutes, AM/PM).
- Enter the end time using the time picker.
- For Date & Time mode, select both the date and time for start and end.
- Click "Calculate Duration" to see the result in hours:minutes:seconds, decimal hours, and total minutes.
Note: In "Time Only" mode, if the end time is earlier than the start time (e.g., 10 PM to 6 AM), the calculator automatically assumes it crosses midnight.
How the Duration Calculation Works
Time-Only Mode (Same Day)
Duration = End Time - Start Time
If end time < start time, add 24 hours (crosses midnight): Duration = (End + 24:00) - Start
Date & Time Mode
Duration = End DateTime - Start DateTime
The result is the total elapsed time across any number of days, hours, and minutes.
Time Duration Examples
| Start | End | Duration | Decimal Hours | Use Case |
|---|---|---|---|---|
| 9:00 AM | 5:00 PM | 8:00:00 | 8.00 hrs | Standard workday |
| 10:00 PM | 6:30 AM | 8:30:00 | 8.50 hrs | Overnight sleep |
| 2:15 PM | 2:15 PM + 2 days | 48:00:00 | 48.00 hrs | Weekend trip |
| 8:45 AM | 12:30 PM | 3:45:00 | 3.75 hrs | Morning meeting |
Frequently Asked Questions
To calculate time duration, subtract the start time from the end time. For simple cases: Duration = End Time - Start Time. If the end time is earlier than the start (crossing midnight), add 24 hours to the end time first. For multi-day durations, convert both dates to total minutes, subtract, then convert back.
Yes! Our calculator automatically handles overnight durations. If you enter a start time of 10:00 PM and an end time of 6:00 AM, it correctly calculates 8 hours (not -16 hours). In Date & Time mode, any crossing of midnight is handled automatically since it uses full date-time values.
Enter your clock-in time as the start and your clock-out time as the end. The calculator will show total hours worked. For lunch breaks, calculate morning and afternoon separately and add them, or use the Date & Time mode to exclude break times by calculating before and after lunch separately.
This calculator shows the difference between two times. To add or subtract time, first calculate the duration, then use the decimal hours value. For example, to add 30 minutes to a 2.5-hour duration, the result is 3.0 hours. Use our Hours Calculator for time addition and subtraction operations.
Disclaimer
This time duration calculator is provided for informational purposes only. Results are based on the times you input and assume consistent time zones. It does not account for daylight saving time transitions, timezone changes, or time rounding policies used by employers.