| .crp |
Cities: Skylines Colossal Raw Asset Package |
| .cma |
Coach Activity File |
| .cdoc |
Encrypted DigiDoc File |
| .clip |
Clip Studio Format File or Grand Theft Auto V Video Game file |
| .crypt12 |
WhatsApp Encrypted Database File |
| .chk |
InterCheck Checksum Database |
| .cin |
Kodak Cineon Bitmap File |
| .cwk |
ClarisWorks Document |
| .cil |
Clip Gallery Packaged File |
| .c01 |
WinAce Split Archive Part 1 File |
| .cwp |
Cakewalk SONAR Project |
| .cdt |
CD-Text File |
| .cvi |
Canvas Image File |
| .cv5 |
Canvas 5 Drawing File |
| .cha |
IRC Chat Configuration File |
| .chat |
IRC Chat Configuration File |
| .cod |
Compiled Source Code |
| .config |
Configuration File |
| .cache |
Cache File |
| .crz |
Compressed Poser Character Rigging File |
| .clkk |
Clicker Keyboard |
| .clkt |
Clicker Template |
| .clkw |
Clicker Word Bank |
| .clkx |
Clicker Grid Set |