| cell | CASTEP Cell Input Data |
| celx | Celestia Script File |
| cen | CEN EN 13032 Photometric Data |
| cert | Netscape Certificate Index |
| cex | SolidWorks Enterprise PDM Exported Vault Settings |
| cez | Prosurv cEZ Job File |
| cf | CFEngine Policy Data |
| cf1 | Common Loudspeaker Format Type 1 File |
| cf2 | Common Loudspeaker Format Type 2 File |
| cf3 | CFEngine Policy Data |
| cf5 | Docuware v5 Content Folder File |
| cf7 | Cashflow Manager v7 Data File |
| cf8 | Cashflow Manager v8 Data |
| cf9 | Cashflow Manager v9 Data |
| cfd | CryptoForge Document |
| cfdg | Context Free Design Grammar |
| cfe | CryptoForge Encrypted |
| cff | Docuware Content Folder File |
| cfgr | BenMAP Configuration Results |
| cfh | Fieldbus Foundation Capabilities Data |
| cfk | Microsoft Developer Studio Diagram |
| cfl | IMVU Product Data |
| cflt | CATS Flat File |
| cfog | Cloudfogger Encrypted Data |
| cfp | Intuit Quickbooks Cash Flow Projector File |
| cfs | Lucene Single Compound File |
| cft | Microsoft SQL Server Data Replication Conflict Tables |
| cfv | CFView Data |
| cfw | ChemFinder Form File |
| cfx | Picasa Collage Data |
| cfx | Lucene 2 Compound File |
| cfx | CFX Case File |
| cgc | Compressed Gamecube Disk Image |
| cgd | CricketGraph Data |
| cgk | BlueSoleil Driver Data |
