Cognomen Karthig (Karthig 
) , in the entire world, is an extremely rare family name. Much more frequently, Karthig is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Karthig | United States, Singapore, India |
Raja, Kumar, David, Gopal, Kanthan, Kogulan, Balendran, Kunasakaran, Kulasegaran, Uthayakumar, and Amirtharajah