- var_dump: documentation ( source)
- date_default_timezone_set: documentation ( source)
<?php
date_default_timezone_set('Europe/Berlin');
$d1 = new DateTime('2021-03-28T01:00:00');
$d2 = new DateTime('2021-03-28T04:00:00');
var_dump($d1, $d2, ($d2->getTimestamp() - $d1->getTimestamp()) / 60);