To calculate the difference or the number of days between two dates, you simply subtract one date from the other.

Example (using format:dd/mm/yyyy):

Suppose you have the date 25/11/2007 in cell A1 and the date 15/01/2008 in cell B1 (both cells formatted as date). To calculate the difference between these two dates you use the following formula:

=B1 – A1

This should give a result of 51 ( 5 days in Nov + 31 in Dec + 15 in Jan).

Note that the cell where you write the formula must be formatted as **number **and not date.