| ribbons | Ribbons Data |
| rif | FRAMES Receptor Intakes File |
| rif | Mikrotik RouterOS Dump |
| riff | Resource Interchange File Format |
| rig | Lightwave 3D RIG Function Data |
| rinex | Receiver Independent Exchange Format Data |
| rio | OMICRON Test Universe RIO Object |
| rip | Lotus Notes Error Data |
| rir | RIR Statistics Exchange Format Data |
| rir8 | Avantes Avasoft v8 Relative Irradiance Mode Data |
| riscos | RISC OS Data |
| rit | DriveClone Data File |
| riv | CRiSP Harvest Data |
| rjs | RealJukebox Skin Data |
| rjt | RealJukebox Track Info Style |
| rki | Race-Keeper Video Index Data |
| rkl | VST-AU Alpha JUNO Editor License Key Data |
| rkn | Reckon Personal Plus Backup Data |
| rkp | RemoteKeys Profile Data |
| rkplr | NI REAKTOR Player Data |
| rks | SOBEK Rainfall Series Data |
| rkv | eXtendable Wad Editor RKV Data |
| rky | SDLX Registration Key Data |
| rl | R.viewer List Data |
| rl | XML Resource Lists Data |
| rl1 | RL-1 Database Data |
| rl7 | PCAnywhere Remote Session Log |
| rld | RecLoad Definition |
| rld | XML Resource Lists Diff Data |
| rlg | RegCleaner Language File |
