Excel: Count Number of Days Between Two Dates Inclusive

You can use the following formula in Excel to calculate the number of days between two dates, including the start date.

=B2-A2+1

This particular formula assumes the start date is in cell A2 and the end date is in cell B2.

For example, if the start date is 1/1/2023 and the end date is 1/2/2023 then this formula will return 2 since there is a difference of two days between these dates including the start date.

The following example shows how to use this formula in practice.

Example: Count Number of Days Between Two Dates Inclusive

Suppose we have the following list of start and end dates in Excel:

Suppose we would like to count the number of days between each start and end date, including the start date.

We can type the following formula into cell C2 to do so:

=B2-A2+1

We can then drag and fill this formula down to each remaining cell in column C:

Excel number of days between two dates inclusive

Column C now displays the number of days between each start and end date, including the start date.

For example:

There are 2 days between 1/1/2023 and 1/2/2023, including the start date.
There are 4 days between 1/15/2023 and 1/18/2023, including the start date.
There are 3 days between 2/1/2023 and 2/3/2023, including the start date.

And so on.

Note: If the start date and end date are the same day, then this formula will return 1 to indicate that there is 1 day that occurs in the date range.