| Name | Gender | Pronounced | Usage | Popularity |
|---|---|---|---|---|
| Koos | KO:S | Dutch | ||
| Koraljka | - | Croatian | ||
| Koresh | - | Biblical Hebrew | ||
| Korinna | - | Ancient Greek | ||
| KornÉLie | - | Czech | ||
| Kornel | KAWR-nel (Polish) | Polish, Czech, Slovak | ||
| Kornelija | - | Croatian, Serbian | ||
| Kosmas | - | Ancient Greek | ||
| Kostadin | - | Bulgarian, Macedonian | ||
| Krasimir | - | Bulgarian, Medieval Slavic | ||
| KreŠImir | - | Croatian | ||
| KreŠImira | - | Croatian | ||
| KreŠO | - | Croatian | ||
| Kresimir | - | Medieval Slavic | ||
| Kreskes | - | Biblical Greek |