Family name Kochaj (Kochaj 
) , around the globe, is a very rare surname. The family name Kochaj is characteristic of Poland, where it is a very rare surname, and the United Kingdom, where it is an extremely rare surname. More prevalently, Kochaj is the forename as well as the last name.
| VARIANT | COUNTRY |
|---|---|
| Kochaj | United Kingdom, Poland |