| Kiki | | KEE-kee (English), kee-KEE (Greek) | English, German, Greek | |
| Kilian | | KEE-lee-ahn (German) | German, Irish, French | |
| Kinge | | KING-ə | German | |
| Klaas | | KLAH:S | Dutch, Low German | |
| Klara | | KLAH-rah (German, Russian, Polish) | Swedish, Norwegian, Danish, Icelandic, German, Russian, Ukrainian, Polish, Slovene, Croatian | |
| Klaus | | KLOWS (German, Finnish) | German, Danish, Norwegian, Finnish | |
| Klemens | | KLE-mens (German, Polish) | German, Danish, Swedish, Polish | |
| Knut | | KNOOT (German) | Swedish, Norwegian, Danish, German | |
| Kolman | | KAWL-mahn | German (Rare) | |
| Koloman | | KO-lo-mahn (German) | German (Rare), Slovak | |
| Konrad | | KAWN-raht (German, Polish) | German, Swedish, Norwegian, Danish, Polish, Slovene | |
| Konstantin | | KAWN-stahn-teen (German), kahn-stahn-TEEN (Russian) | German, Hungarian, Russian, Serbian, Bulgarian, Macedonian | |
| Konstanze | | - | German | |
| Kora | | KO-rah | German | |
| Korbinian | | kawr-BEE-nee-ahn | German | |