| rbz | SketchUp Zipped Ruby Plug-in |
| rcv | Oracle Recovery Manager Script |
| redir | Spotify Executable Redirect |
| reg | Registration Entries |
| regtrans-ms | Windows Registry Transaction Log |
| rej | Patch Reject File |
| ren | Backup Copy File |
| req | Canon Camera Request File |
| rfu | HP Laserjet Printer Remote Firmware Update |
| rfw | Rockchip Firmware |
| rhev | Red Hat Enterprise Virtualization Related Data |
| rhp | Rhino 3D Plugin |
| ri2 | Lowrance Sonar Software Upgrade |
| ril | Android Radio Interface Library |
| riw | Lowrance Sonar Software Upgrade |
| rkp | Rockchip MP4 Player Game |
| rman | Oracle Recovery Manager Script |
| rmn | Oracle Recovery Manager Script |
| rock | Rockbox Plug-in |
| rpi | Kega Fusion Render Plug-in |
| rpj | Real Pac Batch Job |
| rpln | Adobe InDesign Required Plug-in |
| rqf | R-Quest Duplication Systems Firmware Update |
| rra | Windows Installer Temporary File |
| rsa | PKCS7 RSA Signature |
| rsj | Personal Backup Saved Task |
| rsl | Adobe PageMaker Resource |
| rsrc1 | Multiloader RSRC1 Firmware |
| rsrc2 | Multiloader RSRC2 Firmware |
| rtsp | Real Time Streaming Protocol Data |
| rvp | Sharp Blu-ray Player Firmware |
| rwt | HyperRESEARCH Plugin |
| rwz | Microsoft Outlook Rules Wizard |
| rxc | Roxio Certificate |
| rxt | Retrospect Extension |
