$HeureDeb = "06:29"; $HeureFin = "12:03"; $TimeDeb = explode ( ":", $HeureDeb ); $TimeFin = explode ( ":", $HeureFin ); $Duree = date( "H:m", mktime( ($TimeFin[0]-$TimeDeb[0]) , ( $TimeFin[1]-$TimeDeb[1] ) ,0) );