| Name | Gender | Pronounced | Usage | Popularity |
|---|---|---|---|---|
| Klaudio | - | Croatian | ||
| Klaus | KLOWS (German, Finnish) | German, Danish, Norwegian, Finnish | ||
| Klava | - | Russian | ||
| Klavdiya | KLAHV-dee-yah (Russian) | Russian, Ukrainian, Bulgarian | ||
| Kleisthenes | - | Ancient Greek | ||
| Kleitos | - | Ancient Greek | ||
| Klemens | KLE-mens (German, Polish) | German, Danish, Swedish, Polish | ||
| Klementina | - | Slovene, Croatian | ||
| Kleon | - | Ancient Greek | ||
| Kleopatra | - | Ancient Greek | ||
| Kleopatros | - | Ancient Greek | ||
| Klim | - | Russian, Ukrainian | ||
| Kliment | klee-MYENT (Russian) | Russian, Ukrainian, Bulgarian, Macedonian | ||
| Klimentina | - | Macedonian | ||
| Klotild | - | Hungarian |