Published Jul 20, 2023
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The date_diff() function takes two DateTime objects as parameters and determines the difference in time between them. An optional boolean parameter can be set to true to return the absolute value, ensuring that the result is positive. The function returns a DateInterval object that can be formatted as needed.


    DateTimeInterface $dateOne,
    DateTimeInterface $dateTwo
    bool $absolute=false
): DateInterval

The $dateOne and $dateTwo parameters are DateTime objects as returned by date_create(). Because the returned value is a DateInterval object, date_format() cannot be used to format the result. The DateInterval::format() function can be used for formatting using the characters below. The formatting characters must be prefixed with a percent sign (%).

Character Description
Y Number of years, at least two digits with leading zero
y Number of years
M Number of months, at least two digits with leading zero
m Number of months
D Number of days, at least two digits with leading zero
d Number of days
a Total number of days
H Number of hours, at least two digits with leading zero
h Number of hours
I Number of minutes, at least two digits with leading zero
i Number of minutes
S Number of seconds, at least two digits with leading zero
s Number of seconds
F Number of microseconds, at least six digits with leading zero, always positive
f Number of microseconds, always positive
R Sign (+, -)
r Sign, empty when positive


The example below creates two DateTime objects, then prints the difference with format strings.

$dateOfBirth = date_create("3/27/2001 4:30pm");
$dateNow = date_create("now");
$diffSinceBirth = date_diff($dateOfBirth, $dateNow);
echo $diffSinceBirth->format("%y years, %m months, %d days, %h hours, and %i minutes since birth.\n");
echo $diffSinceBirth->format("%a days since birth.");

This code results in different output each time it is executed, but it will be similar to this:

22 years, 3 months, 16 days, 22 hours, and 11 minutes since birth.
8143 days since birth.

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