$re = '/(?<!\d)(?<!\d[,.])(?:\d{1,3}(?:[. \xA0]\d{3})*|\d+)(?:,\d+)?(?![.,]?\d)/m';
$str = '120.000,00
120 000,00
40 000
456.667
334532
123 223 333,345555';
preg_match_all($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