Comparing two dates in PHP

Given two dates (date1 and date2) and the task is to compare the given dates. Comparing two dates in PHP is simple when both the dates are in the same format but the problem arises when both dates are in a different format.

Method 1: If the given dates are in the same format then use a simple comparison operator to compare the dates.

Example:

<?php
// PHP program to compare dates

// Declare two dates and
// initialize it
$date1 = "1998-11-24";
$date2 = "1997-03-26";

// Use comparison operator to
// compare dates
if ($date1 > $date2)
    echo "$date1 is latest than $date2";
else
    echo "$date1 is older than $date2";

?>

Output:

1998-11-24 is latest than 1997-03-26

Method 2: If both of the given dates are in different formats then use strtotime() function to convert the given dates into the corresponding timestamp format and lastly compare these numerical timestamps to get the desired result.

Example:

<?php
// PHP program to compare dates

// Declare two dates in different
// format
$date1 = "12-03-26";
$date2 = "2011-10-24";

// Use strtotime() function to convert
// date into dateTimestamp
$dateTimestamp1 = strtotime($date1);
$dateTimestamp2 = strtotime($date2);

// Compare the timestamp date
if ($dateTimestamp1 > $dateTimestamp2)
    echo "$date1 is latest than $date2";
else
    echo "$date1 is older than $date2";

?>

Output:

12-03-26 is latest than 2011-10-24

Method 3: Using DateTime class to compare two dates.

Example:

<?php
// PHP program to compare dates

// Declare two dates in different
// format and use DateTime() function
// to convert date into DateTime
$date1 = new DateTime("12-11-24");
$date2 = new DateTime("2011-03-26");

// Compare the dates
if ($date1 > $date2)
    echo $date1->format("Y-m-d") . " is latest than "
            . $date2->format("Y-m-d");
else
    echo $date1->format("Y-m-d") . " is older than "
            . $date2->format("Y-m-d");

?>

Output:

2012-11-24 is latest than 2011-03-26

PHP is a server-side scripting language designed specifically for web development. You can learn PHP from the ground up by following this PHP Tutorial and PHP Examples.