When I do the following code:
<?php
echo strtotime(str_replace("/", "-", "18/05/2018 15:00:11");
?>
I get:
1526670011
This way, try to use the normal syntax of date and time and get two times this way:
<?php
echo strtotime(str_replace("/", "-", "18/05/2018 14:00:00"));
echo "<br />";
echo strtotime(str_replace("/", "-", "18/05/2018 15:00:00"));
echo "<br />";
echo strtotime(str_replace("/", "-", "18/05/2018 15:00:00")) - strtotime(str_replace("/", "-", "18/05/2018 14:00:00"));
?>
You get in seconds.
1526666400
1526670000
3600
Convert them into minutes by dividing it by 60.
<?php
$start = "18/05/2018 14:00:00";
$end = "18/05/2018 15:00:00";
echo strtotime(str_replace("/", "-", $start));
echo "<br />";
echo strtotime(str_replace("/", "-", $end));
echo "<br />";
echo strtotime(str_replace("/", "-", $end)) - strtotime(str_replace("/", "-", $start)) . " seconds";
echo "<br />";
echo (strtotime(str_replace("/", "-", $end)) - strtotime(str_replace("/", "-", $start)))/60 . " minutes";
You get something like:
1526666400
1526670000
3600 seconds
60 minutes
Hope this helps.