Time Duration Calculator

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0 hours, 00 minutes

Instructions for using the time duration calculator

Use this time duration calculator to calculate the number of days and hours between two times, or the duration between two dates. Here are instructions on how to use the time duration calculator:

Step 1. Enter your start date and time, and end date and time

Step 2. Click the “Calculate Time Duration” button

Including work hours in your calculation

If you want to calculate working hours between two times, then you can use the “work hours” table to select which hours you want to include or exclude from the calculation. Activate the work hours table by ticking the box that says “Display Work Hours.”

Here’s how it works:

  • Each box within the matrix represents one hour of time. Tick all the boxes that correspond to the days and hours that you want to include in the calculation (your work hours).
  • Any hours represented by unchecked boxes will not be included in the calculation. In other words, only hours represented by ticked boxes will be included in the calculation.


Let’s say I receive an email on April 1st, 2020, at 4pm. And let’s say I respond to that email on April 2nd at 3pm, and I want to calculate the duration of time that it took me to respond to that email, but I only want to count the number of hours I was actually on the clock (work hours) that elapsed during that time.

My work hours are Monday through Friday, from 8am to 5pm. I take a lunch break at noon every day, so my work hours chart looks like this:

work hours table example

Notice how I left un-ticked all the boxes in the “12pm-1pm” timeslot, which represents my lunch time!

I set my start date/time and end date/time accordingly:

start date end date

Now, when I click the “Calculate time duration” button, the tool calculates the duration between two times and dates for only the selected work hours.

Result: In this case, for my example, the result is 7 hours, 0 minutes.


  1. While the “work hours” table is hidden, no work hours will be included in your calculation. In other words, your result will be the actual number of days and hours between the two times.
  2. If your start date/time occurs outside of your defined work hours, then the duration calculation will begin at the start of your next defined work hour.
  3. If your end date/time occurs outside of your defined work hours, then the duration calculation will end at the end of the preceding defined work hour.
  4. This time duration calculator app simulates how we calculate your average email response time in our flagship app, EmailAnalytics!