Cognomen แดงฤทธิ์ (แดงฤทธิ์ 
, Daengrit ) , throughout the world, is a very rare family name. The family name แดงฤทธิ์ is characteristic of South-eastern Asia, particularly Thailand, where it is a rare surname. Very seldom, แดงฤทธิ์ is the forename as well as the last name.