Note that the DATEDIF automatically rounds down. To round up to the nearest month, see below.
The mystery of DATEDIF
The DATEDIF function is a "compatibility" function that comes from Lotus 1-2-3. For reasons unknown, DATEDIF is only documented in Excel 2000, and will not appear as a suggested function in the formula bar. However, you can use DATEDIF in all Excel versions since that time, you just need to enter the function manually. Excel will not help you with function arguments. See this page on the DATEDIF function for more information about available arguments.
How this formula works
DATEDIF takes 3 arguments: start date, end_date, and unit. In this case, we want months, so we supply "m" for unit.
DATEDIF automatically calculates and returns a number for months, rounded down.
Nearest whole month
DATEDIF rounds down by default. If you want to calculate months to the nearest whole month, you can make a simple adjustment to the formula:
T calculate the number of days between two dates you can simply subtract the older date from the newer date. The result will be an integer that represent the days between dates. In the example shown, the formula in D6 is: = C6 - D6 The result is 365...
To calculate the number of workdays between two dates, you can use the NETWORKDAYS function. NETWORKDAYS automatically excludes weekends, and it can optionally exclude a custom list of holidays as well. For example, if you have the date January 4,...
The Excel DATEDIF function returns the difference between two date values in years, months, or days. The DATEDIF (Date + Dif) function is a "compatibility" function that comes from Lotus 1-2-3. For reasons unknown, it is only documented in Excel...
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