What is the Time Duration Calculator?
The time duration calculator is a free online tool that helps you work out time duration quickly and accurately. It uses the standard formula Duration = end - start - break (handles crossing midnight) and shows the result instantly as you type, along with a full breakdown so you can see exactly how the answer was reached.
How to use this calculator
- Enter the start time.
- Enter the end time.
- Add any break.
- See the duration.
Formula used
Duration = end - start - break (handles crossing midnight)Explanation of each input
- Start time (HH:MM) โ the start time (hh:mm) used in the calculation.
- End time (HH:MM) โ the end time (hh:mm) used in the calculation.
- Break (minutes) โ the break (minutes) used in the calculation.
Understanding your result
- Duration โ the calculated duration in hours.
- Hours & minutes โ the calculated hours & minutes.
Step-by-step calculation
For the example values 09:00 to 17:30, 30 min break:
- Apply the formula:
Duration = end - start - break (handles crossing midnight) - Substitute the values: 8.5 - 0.5
- Result: 8 hours
Worked example
| Inputs | 09:00 to 17:30, 30 min break |
|---|---|
| Working | 8.5 - 0.5 |
| Result | 8 hours |
Benefits and practical uses
This calculator saves you time and reduces errors when you need time duration. It is useful for students, professionals and anyone who wants a fast, reliable answer without manual calculation. Results update instantly, work in your browser and can be copied or shared in one click.
Assumptions and limitations
- 24-hour HH:MM format.
Frequently asked questions
Does it handle overnight shifts?
Yes - if the end time is earlier than the start, it assumes the next day.
Disclaimer: Results are provided for general information. Please verify important figures independently.