Calculate the time duration between two times or dates with our free online calculator. Get instant results in hours, minutes, seconds, and decimal format. Perfect for calculating work hours, tracking project time, processing payroll, billing clients, and managing employee schedules. Handles overnight shifts, cross-midnight times, and multi-day durations automatically.
Enter the starting time using hour, minute, and second fields. Select AM or PM. Click “Now” to use the current time.
Enter the ending time in the same format. The calculator automatically handles times crossing midnight.
Enter the starting time using hour, minute, and second fields. Select AM or PM. Click “Now” to use the current time.
Get comprehensive results in hours, minutes, seconds, and decimal hours perfect for payroll.
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Calculating the duration between two times can be a little tricky depending on the numbers of minutes and seconds in the two times being compared. As an example, the following are the steps to determine the number of hours and minutes between two chosen times within the same day:
Step-by-Step Process
13:57 – 9:22 ——– 4:35
If the starting time has a larger number of minutes: Treat the hour and minute portion separately. Add 60 to the number of minutes in the ending time, and subtract 1 hour from the hour portion of the ending time. Then, subtract the minutes and the hours, keeping the result on the appropriate side of the “:” where hours are on the left, and minutes are on the right. For example:
13:57 12:117 – 9:58 => – 9:58 ——– ——— 3:59
The key to calculating time duration accurately is understanding how to handle minutes and seconds that “carry over” or “borrow” between units. When the ending time’s minutes are less than the starting time’s minutes, you need to borrow 60 minutes from the hours column.
This is similar to how you would subtract regular numbers, but instead of borrowing by 10s (as in regular base-10 math), you’re borrowing by 60s since there are 60 minutes in an hour and 60 seconds in a minute.
Our calculator uses the 12-hour AM/PM format for ease of use, but internally converts to 24-hour format for accurate calculations:
This conversion ensures accurate calculations regardless of whether times cross noon or midnight.
Example 1: Standard Work Day
Start: 8:30 AM, End: 5:30 PM
Result: 9 hours exactly
Example 2: Overnight Shift
Start: 10:00 PM, End: 6:00 AM
Result: 8 hours (night shift crossing midnight)
Example 3: Meeting Duration
Start: 2:15 PM, End: 3:45 PM
Result: 1 hour 30 minutes (1.5 decimal hours)
