- time: documentation ( source)
- mktime: documentation ( source)
- date_parse_from_format: documentation ( source)
<?php
$date = '09-19-2017';
$parsed = date_parse_from_format('m-d-Y', $date);
$timestamp = mktime(
$parsed['hour'],
$parsed['minute'],
$parsed['second'],
$parsed['month'],
$parsed['day'],
$parsed['year']
);
if ($timestamp < time()) {
echo 'older';
} else {
echo 'newer';
}