Cognomen ฤทธิเพชร (ฤทธิเพชร 
, Rittiphet , Rittipet ) , all around the world, is a rare surname. The family name ฤทธิเพชร is habitual in South-eastern Asia, particularly Thailand, where it is a rare surname.
| VARIANT | COUNTRY |
|---|---|
| Rittipet, Rittiphet, ฤทธิเพชร | Thailand |
Ritthiphet, Ritthiphetr, and Rittipetch