| Name | Gender | Pronounced | Usage | Popularity |
|---|---|---|---|---|
| Kitty | KIT-ee | English | ||
| Kizzie | KIZ-ee | English | ||
| Kizzy | KIZ-ee | English | ||
| Klara | KLAH-rah (German, Russian, Polish) | Swedish, Norwegian, Danish, Icelandic, German, Russian, Ukrainian, Polish, Slovene, Croatian | ||
| Klavdija | - | Slovene | ||
| Kleisthenes | - | Ancient Greek | ||
| Kleitos | - | Ancient Greek | ||
| Klemen | - | Slovene | ||
| Klementina | - | Slovene, Croatian | ||
| Kleon | - | Ancient Greek | ||
| Kleopatra | - | Ancient Greek | ||
| Kleopatros | - | Ancient Greek | ||
| KnÚTr | - | Ancient Scandinavian | ||
| Knox | NAHKS | English | ||
| Koby | KO-bee | English (Modern) |