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 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 before noon, there’s nothing to do for this step since the time is already in 24-hour time. If the time is 1:00 pm or later, then add 12 to the hours 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 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 From the End

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 in hours as a decimal. You can use our hours to time converter to get the elapsed time in hours and minutes.

To calculate the number of days between two dates you can use our day counter or select the “duration between dates” tab above.