Cognomen 恺昀 (恺昀 
) , in the world, is a very rare last name. The cognomen 恺昀 is habitual in Eastern Asia, particularly China, where it is an extremely rare surname. More frequently, 恺昀 is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| 恺昀 | China |