Time Duration Calculator
Calculate the elapsed time between two times, two dates, or two dates and times using the duration calculator below.
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How to Calculate Elapsed Time
Whether you’re trying to track the hours you’ve worked or how long your puppy has been without water, you can calculate the duration of elapsed time between two different times by following a few simple steps.
Step One: Convert Both Times to 24-Hour Time
If the time is earlier than noon, simply remove the colon in the time and drop the “am”. If the time is 1:00 pm or later, then add 12 to the hours, drop the colon, and remove the “pm” from the end of the time.
Step Two: Convert Time to Decimal Hours
Next, you’ll need to convert each time to decimal hours. Simply divide the number of minutes by 60 to get the decimal portion of the hours, or use a time to decimal calculator as a shortcut.
Step Three: Subtract the Start Time From the End Time
Finally, subtract the decimal start time from the end time to get the duration of elapsed time.
The result will be the duration of time elapsed in hours as a decimal. You can then use our hours to time converter to convert the elapsed time in hours and minutes.