

It stores each date as a number calculated as the number of days from, so that Januis “1” and all subsequent dates are successively higher numbers. What a lot of people don’t realize is that Microsoft Excel doesn’t actually store dates per se. This is done using the DATEVALUE function:

If, however, the dates are not anywhere else in the spreadsheet, you’ll have to embed them in the formula itself. If they are, then the formula needed to perform the calculation is actually very simple (assuming you already know how to do simple formulas in Microsoft Excel):

I say “deceptively simple” because the answer depends upon the context, namely, whether the two dates being compared are actually embedded in cells within the Microsoft Excel spreadsheet. A reader contacted me recently with a deceptively simple Microsoft Excel question: “How do I calculate the difference between two dates?”
