$re = '/^(?<start>(?<starthour>[0-9]+)(?:[:\.](?<startminute>[0-9]+))?)(?:[\s]*(?:[-—]|bis|Uhr)[\s]*)*(?<end>(?<endhour>[0-9]+)(?:[:\.](?<endminute>[0-9]+))?)(?:[\s]*(?:Uhr)[\s]*)?$/m';
$str = '07:00 - 15:30
16:00 bis 20:30
7:00-15:00
7.00 Uhr 16.30 Uhr
7 - 16.30 Uhr
7 - 16 Uhr
7:30 - 16 Uhr
7:15 Uhr bis 16:30 Uhr
7-16.15 Uhr';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php