| r2k | Repertoire 2000 Music Database |
| r2lang | Rainlendar v2 Language Data |
| r2lic | Rainlendar v2 License Data |
| r2s | Green Kenue Rectangular Data |
| r2skin | Rainlendar Skin |
| r2v | Green Kenue Rectangular Data |
| r2v3 | Adobe Streamline Data |
| r3d | CorelDream 3D Data |
| r3df | CorelDream 3D Data |
| r3f | SAP R/3 Form Data |
| r8 | Cubicomp PictureMaker Red Channel Image Data |
| r99 | MicroStation Modification System Resource File |
| raa | RiTE Ascii Animation |
| rab | Encyclopaedia Britannica 2002 Deluxe Data |
| rac | Racter Conversation Data |
| rac | UltraEdit Autorecovery Data |
| rac | Venue Race Application Race Data |
| rad | RFM Radiance Spectrum File |
| rag | RAM Advanse Data File |
| rai | SPEFO Stellar Spectra Analysis Data |
| ral | Atlas Right Track Layout |
| ral | WinRail Layout Data |
| ram | RiTE Ascii Model |
| rap | GSM Returned Accounts Procedure Data |
| raq | Cobalt RAQ Backup Data |
| ras | RiTE Ascii Shader Information |
| raskinlicense | Raskin License Data |
| rat | Nimbus 7 SAMS CRAT File |
| rat | PICS Service Description |
| raw | 3DCS Simulation RAW Data |
| raw | Bruker RAW Data |
| raw | Nimbus 7 SAMS Raw Data |
| raw | PLINK Additive and Dominant Component Data |
| raw8 | Avantes Avasoft v8 Scope Mode Data |
| rawpkt | Colasoft Capsa Capture Data |
