Time Duration Calculator
Calculate the elapsed time between two times, two dates, or two dates and times using the duration calculator below.
Time Duration:
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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
The first thing you need to do to calculate time duration is to convert the start and end times to 24-hour time, which is often referred to as military 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.
To calculate the number of days between two dates you can use our day counter, days until date calculator, or select the “duration between dates” tab above.