| CAI (1) m Scandinavian |
| CAJ m Scandinavian |
| CEES m Dutch |
| COKKIE f Dutch |
| CORA f English, German |
| COREEN f English (Rare) |
| CORETTA f English |
| COREY m English |
| CORI f English |
| CORIE f English |
| CORINA f English, German, Romanian |
| CORINE f English |
| CORINNA f English, German, Ancient Greek (Latinized) |
| CORINNE f French, English |
| CORNÉ m Dutch |
| CORNEILLE m French (Archaic) |
| CORNEL m Romanian |
| CORNELIA f English, Italian, German, Dutch, Romanian, Ancient Roman |
| CORNÉLIE f French |
| CORNÉLIO m Portuguese |
| CORNELIO m Spanish, Italian |
| CORNELIS m Dutch |
| CORNELIU m Romanian |
| CORNELIUS m Ancient Roman, English, Dutch, German, Biblical |
| CORNELL m English |
| CORRIE f English, Dutch |
| CORRINA f English |
| CORRINE f English |
| CORY m English |
| CORYNN f English (Rare) |
| KAI (1) m Frisian, German, Scandinavian, Finnish, Dutch |
| KAJ (1) m Scandinavian |
| KAY (3) m Frisian, German, Scandinavian |
| KEES m Dutch |
| KERNEELS m Dutch |
| KORA f German |
| KORË f Greek Mythology |
| KOREY m English |
| KORI f English |
| KORINA f Greek |
| KORINNA f Ancient Greek |
| KORNÉL m Hungarian |
| KORNEL m Polish, Czech, Slovak |
| KORNÉLIA f Hungarian |
| KORNELIA f German, Polish |
| KORRINE f English (Rare) |
| KORY m English |
| NELE f German |
| NIELS (2) m Dutch |
