PHP: Days since today or days between two dates

Source code viewer
// Define start date, from which we want to start the count.
$start_date = new DateTime("2016-01-14");
// Current date, to do the difference calculation.
$current = new DateTime(date('Y-m-d'));
 
// Calculate difference of the dates and show the difference in days.
$days = (int) $current->diff($start_date)->format("%a");
 
// If the days are divisible by 4.
if (!($days % 4)) {
  // ...
}
Programming Language: PHP