DATEDIF

Calculates the number of days, months, or years between two dates. This function is provided for compatibility with Lotus 1-2-3.

Syntax

DATEDIF(start_date,end_date,unit)

Start_date A date that represents the first, or starting, date of the period. Dates may be entered as text strings within quotation marks (for example, "2001/1/30"), as serial numbers (for example, 36921, which represents January 30, 2001, if you're using the 1900 date system), or as the results of other formulas or functions (for example, DATEVALUE("2001/1/30")).

End_date A date that represents the last, or ending, date of the period.

Unit The type of information you want returned:

Unit	Returns
"Y"	The number of complete years in the period.
"M"	The number of complete months in the period.
"D"	The number of days in the period.
"MD"	The difference between the days in start_date and end_date. The months and years of the dates are ignored.
"YM"	The difference between the months in start_date and end_date. The days and years of the dates are ignored
"YD"	The difference between the days of start_date and end_date. The years of the dates are ignored.

Remarks

Dates are stored as sequential serial numbers so they can be used in calculations. By default, December 31, 1899 is serial number 1, and January 1, 2008 is serial number 39448 because it is 39,448 days after January 1, 1900.
The DATEDIF function is useful in formulas where you need to calculate an age.

Example

Start_date	End_date	Formula	Description (Result)
1/1/2001	1/1/2003	DATEDIF(Start_date,End_date,"Y")	Two complete years in the period (2)
6/1/2001	8/15/2002	DATEDIF(Start_date,End_date,"D")	440 days between June 1, 2001, and August 15, 2002 (440)
6/1/2001	8/15/2002	DATEDIF(Start_date,End_date,"YD")	75 days between June 1 and August 15, ignoring the years of the dates (75)
6/1/2001	8/15/2002	DATEDIF(Start_date,End_date,"MD")	The difference between 1 and 15 — the day of start_date and the day of end_date — ignoring the months and the years of the dates (14)