How to compare two dates in php [duplicate]

Question

You will have to make sure that your dates are valid date objects.

Try this:

$date1=date('d/m/y');
$tempArr=explode('_', '31_12_11');
$date2 = date("d/m/y", mktime(0, 0, 0, $tempArr[1], $tempArr[0], $tempArr[2]));

You can then perform the strtotime() method to get the difference.

Using DateTime::createFromFormat:

$format = "d_m_y";
$date1  = \DateTime::createFromFormat($format, "03_01_12");
$date2  = \DateTime::createFromFormat($format, "31_12_11");

var_dump($date1 > $date2);

Not answering the OPs actual problem, but answering just the title. Since this is the top result for "comparing dates in php".

Pretty simple to use Datetime Objects (php >= 5.3.0) and Compare them directly

$date1 = new DateTime("2009-10-11");
$date2 = new DateTime("tomorrow"); // Can use date/string just like strtotime.
var_dump($date1 < $date2);

The date_diff() function returns the difference between two DateTime objects.

If the first date is before the second date a positive number of days will be returned; otherwise a negative number of days:

<?php
$date1=date_create("2013-03-15");
$date2=date_create("2013-12-12");
$diff=date_diff($date1,$date2);
echo $diff->format("%R%a days");
?>

output will be "+272 days" ;

changing $date1 = "2014-03-15"

 <?php
    $date1=date_create("2014-03-15");
    $date2=date_create("2013-12-12");
    $diff=date_diff($date1,$date2);
    echo $diff->format("%R%a days");
    ?>

Output will be "-93 days"

<?php
       $expiry_date = "2017-12-31 00:00:00"
       $today = date('d-m-Y',time()); 
       $exp = date('d-m-Y',strtotime($expiry_date));
       $expDate =  date_create($exp);
       $todayDate = date_create($today);
       $diff =  date_diff($todayDate, $expDate);
       if($diff->format("%R%a")>0){
             echo "active";
       }else{
           echo "inactive";
       }
       echo "Remaining Days ".$diff->format("%R%a days");
?>