There are a lot of methods. The method suggested by "anonymous monk" is ok. Recently I used this way, with "Time::Piece". 
#format first date (get by localtime(time) )
my $date_1 = Time::Piece ->strptime($date, "%Y%m%d%H%M");
#format second date (get by localtime(time) )
my $date_2 = Time::Piece ->strptime($date2", "%Y%m%d%H%M");
#get the diff in seconds
my $diff = $date_1 - $date_2;

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In reply to Re: How to compare two dates? by DanBev
in thread How to compare two dates? by CountOne

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