| rgmb | RootsMagic v4 Database Backup |
| rgmc | RootsMagic v4 Database |
| rgn | Garmin Region File |
| rgp | RealArcade Game Package |
| rgrp | Avid Pro Tools Region Group File |
| rgt | Intuit Quickbooks Temporary File |
| rgv | Borland Caliber Requirement Grid Filter |
| rhd | Standard Intan RHD2000 Header Data |
| rhf | Adobe RoboHelp for FrameMaker Project |
| rhm | Deep Exploration Material Data |
| ri | Lotus 1-2-3 Data File |
| rib | RenderMan RIB Data |
| rif | FRAMES Receptor Intakes File |
| riff | Resource Interchange File Format |
| rinex | Receiver Independent Exchange Format Data |
| rio | OMICRON Test Universe RIO Object |
| rir | RIR Statistics Exchange Format Data |
| rit | DriveClone Data File |
| riv | CRiSP Harvest Data |
| rjt | RealJukebox Track Info Style |
| rkl | VST-AU Alpha JUNO Editor License Key Data |
| rky | SDLX Registration Key Data |
| rld | RecLoad Definition |
| rlg | RegCleaner Language File |
| rlist | PLINK Rare Genotype List File |
| rlt | ReliaSoft Weibull++ Template |
| rlw | ReliaSoft Weibull++ Page |
| rlx | XMetaL Author Rules Data |
| rm2 | Hammer Reminders Data |
| rm2db | ReefMaster Workspace |
| rm3d | RiskMetrics RiskManager Data |
| rm7 | Casio WK-6500 Registration Memory Data |
| rma | Rhapsody DRM License Data |
| rmat | EUHEDRAL Reciprocal Axes Matrix Data |
| rmb | RegistryMaster Data |
