Cognomen มรกฎ (Rule 
, มรกฎ 
) , across the world, is a common family name. The family name มรกฎ is habitual in Australia, where it is quite a rare surname, New Zealand, and Cyprus. In absolute terms, it is the most numerous in the United States, Philippines, and Australia. Very seldom, มรกฎ is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Rule | Australia, Philippines, United States, India, United Kingdom |
| มรกฎ | Thailand |