Surname 神代 (Kojiro 
, Kajiro 
, 神代 , among others...) , across the world, is a rare family name. The cognomen 神代 is habitual in Japan, where it is a rare surname, Hong Kong, and Indonesia, where it is a very rare surname. Not in comparison with a country's population, the name is most common in Japan, Indonesia, and China. Predominantly, 神代 is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Kojiro | Japan, China, Indonesia, United States, Brazil |
| Kajiro | Japan, China, United States, Tanzania, Brazil |
| 神代 | China |
| Какуми | Russia |