- strtotime: documentation ( source)
<?php
$in = "07:07";
$out = "15:56";
$in_time = "07:00";
$out_time = "16:00";
if(strtotime($in) > strtotime($in_time)){
echo (strtotime($in) - strtotime($in_time))/60 . " minutes late in\n\n";
}else{
echo "not late in\n\n";
}
if(strtotime($out) < strtotime($out_time)){
echo (strtotime($out_time)-strtotime($out))/60 . " minutes early out\n";
}else{
echo "not early out\n";
}