In php how to check if one date (given as string) differs to another date at least tree month (unable to find any examples): $date1 = "2013-11-05"; $date2 = "2013-11-19"; //both dates is in form yyyy.mm.dd differsTreeMonths($date1,$date2) { ???? return $differs; } differsTreeMonths("2013-11-05","2014-05-02");//true differsTreeMonths("2014-01-01","2014-04-01");//true differsTreeMonths("2014-01-01","2014-03-31");//false differsTreeMonths("2013-12-01","2014-01-15");//false etc Thank you