Clock Duration Calculator
Calculate the duration between two times on a 12-hour or 24-hour clock. Perfect for figuring out time spans within a single day.
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About the Clock Duration Calculator
The Clock Duration Calculator is a practical tool for finding the amount of time that has passed between a start time and an end time. It's perfect for calculating work shifts, tracking time spent on tasks, or figuring out the duration of an event, all within a 24-hour cycle.
How Does the Calculator Work?
The calculator takes two inputs: a start time and an end time. It then calculates the difference between them and displays the result in hours and minutes.
The Core Logic
The calculation is based on converting both the start and end times into a universal format, like milliseconds, and then finding the difference.
- Time Conversion: Both the start and end times you select are converted into their millisecond equivalents from the beginning of a day.
- Calculate Difference: The calculator subtracts the start time's millisecond value from the end time's millisecond value.
- Handle Overnight Durations: A special rule is applied: if the end time is earlier than the start time (e.g., starts at 10:00 PM and ends at 6:00 AM), the calculator assumes the duration crosses midnight and adds 24 hours to the calculation to get the correct result.
- Convert to Hours and Minutes: The final difference in milliseconds is converted back into hours and minutes for a clear and understandable result.
Practical Examples
Here are a few common use cases:
Example 1: Calculating a Work Shift
- Start Time: 9:00 AM
- End Time: 5:30 PM
- Result: The calculator will show a duration of 8 hours and 30 minutes.
Example 2: Calculating an Overnight Shift
- Start Time: 11:00 PM
- End Time: 7:00 AM
- Result: Because the end time is earlier than the start time, the calculator assumes it's the next day and correctly calculates a duration of 8 hours.
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