In the world, Gajko (Gajko 
, Гайко 
) is a very rare boy's forename. The given name Gajko is characteristic of Eastern Europe, particularly Russia, where it is an extremely rare male name. More prevalently, Gajko is the last name as well as the forename.
| VARIANT | COUNTRY |
|---|---|
| Gajko | Germany, United States, Poland, Brazil, Slovakia |
| Гайко | Kazakhstan, Russia, Kyrgyzstan, Belarus, Ukraine |