$re = '/^\d{1,3}(?:\.\d{3})*(?:,\d+)?$|^\d+(?:,)?\d+$/m';
$str = '1.000,00
.000,00
.000.000,00
0.000,00
111
111,11
111.111,11
11.111.110,00
11.1111.11,00
111
11.11
1111.00
10111111,00
111.000,
11.111,00
111111,00
10.000,00000000
1000.100.00
1.000.000,00
12.345,67';
preg_match_all($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