Determines the integer number of datepart units by which date1 is less than date2.

dateDiff(datepart, date1, date2) → returns numeric

Member Function Syntax

date1.diff(datepart, date2)

dateDiff Argument Reference

datepart string

yyyy: Year
q: Quarter
m: Month
y: Day of year
d: Day
w: Week
ww: Week
h: Hour
n: Minute
s: Second
  • yyyy
  • q
  • m
  • y
  • d
  • w
  • ww
  • h
  • n
  • s

date1 date

date2 date



Member function is available in CF11+.


Member function is available in Lucee4.5+. The Lucee member function diffs dates in the opposite direction (+/-) than the Adobe CF member function. See the example below.

Examples sample code invoking the dateDiff function

dateDiff Example

Find the difference between two dates.

dateDiff("d", "2013-01-15", "2013-01-25")

Expected Result: 10

How old are they?

Calculates a persons age based on a variable birthDate which contains a date. Uses the now function to get current date.

dateDiff("yyyy", birthDate, now())

dateDiff member function

Note the different behavior between ColdFusion and Lucee.

testDate = now();
diffDate = dateAdd('d', 1, testDate);
writeOutput(testDate.diff('d', diffDate)); // this returns 1 on Lucee, and -1 on ColdFusion

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