- Caesar
- Caleb
- Calendau
- Calidius
- Calixtus
- Callinicus
- Callistus
- Callum
- Camillus, Camille
- Carl
- Carsten
- Casimir
- Casper/Jasper
- Cauã
- Célian
- Côme
- Cedric
- Cem
- Chad
- Chaim
- Charles
- Christer
- Christian
- Christopher
- Christos
- Cieszygor
- Cillian, Killian
- Clair
- Clarence
- Clement
- Clovis
- Coby
- Cole
- Colin, Collin
- Colm, Colmán
- Connor, Conor
- Conrad, Cord,
- Constantine
- Corbinian
- Corentin
- Cornelius
- Cristobal
- Csaba
- Csongor
- Ctibor
- Ctirad
- Cyprian
- Cyrus
- Czech
- Czesław