DiFerencia entre Dias Php - con date_diff ()
<?php
// Creates DateTime objects
$datetime1 = date_create('17-09-2018');
$datetime2 = date_create('25-09-2018');
// Calculates the difference between DateTime objects
$interval = date_diff($datetime1, $datetime2);
// Display the result
echo $interval->format('Difference between two dates: %R%a days');
?>
Juan Jose Gonzalez