$re = '/^\d{0,10}?(\.)?(\d{1,2})?$/m';
$str = '123
12345678901
1234567890.00
111.12
123455
.90
.0
.
.900
1234567890
1234567890.1
1234567890.90
111.12
123455
.90
.900
1234567890.00
12345678901.90
123456789011
1234567890111';
preg_match_all($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