| Caroline | | ka-ro-LEEN (French), KER-ə-lien (English), KER-ə-lin (English), KAR-ə-lien (English), KAR-ə-lin (English) | French, English, German, Swedish, Norwegian, Danish, Dutch | |
| Carolus | | - | Ancient Germanic (Latinized) | |
| Carsten | | KAHR-sten (Low German) | Low German, Danish | |
| Casimiro | | - | Spanish, Portuguese, Italian | |
| Caspar | | - | Judeo-Christian Legend | |
| Casper | | KAHS-pər (Dutch) | Dutch, Swedish, Norwegian, Danish | |
| Cassander | | - | Ancient Greek (Latinized) | |
| Cassandra | | kə-SAN-drə (English), kə-SAHN-drə (English), kahs-SAHN-drah (Italian) | English, Spanish, Portuguese, Italian, French, German, Greek Mythology (Latinized) | |
| Cassia | | KA-shə (English) | Ancient Roman | |
| Cassian | | KASH-ən (English) | Ancient Roman (Anglicized) | |
| Cassianus | | - | Ancient Roman | |
| Cassius | | KASH-əs (English), KAS-ee-əs (English) | Ancient Roman, English | |
| Catahecassa | | - | Native American, Shawnee | |
| Catalina | | kah-tah-LEE-nah | Spanish | |
| Catarina | | kah-tah-REE-nah (Italian), ka-ta-REE-na (Galician) | Italian, Portuguese, Occitan, Galician | |