$re = '/(?=.*\d)^(Rp|Rp )?(([1-9]\d{0,2}((\.\d{3})*|\d+))|(0+[1-9]+(\d+|(\.\d{3})*)))(,\d{1,2})?$/m';
$str = '18.215
Rp17500
Rp17.500,00
Rp 120.325
005.000.000.100
001100
10
20000000
100000000
100000001
1000
3000 Rp
Rp
0.999
-1,000
-10
1.1000
17,500
2 500
005.1a2
ram123.12213
ramdan890.9090909';
preg_match_all($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