| rqt | NPrinting Offline Activation Request Data |
| rqx | RiALITY Quick Exchange Data |
| rra | vRigger Rigging Gear |
| rrb | Registrar v3 Bookmark Data |
| rrbm | Registrar v4 Bookmark Data |
| rrd | RapidReader Document |
| rrd | RRDtool Round Robin Database |
| rrd | WAsP Roughness Description |
| rrd4j | RRD4J Graph Data |
| rrds | VSE/VSAM Fixed-Length Records Data |
| rrec | PlasmaEPG Recording State Data |
| rrf | MIKE 11 HD Results Data |
| rrg | JRiver Media Center License File |
| rri | SPEFO Stellar Spectra Analysis Binary RRI Data |
| rrl | Road Runner Data |
| rro | Risk Reduction Overview Data |
| rrp | Rhythm Rascal Project |
| rrp | Running Time Logger Profile |
| rrp | Vflo Precipitation Data |
| rrpa | Oracle Reports Remote Printing Utility Data |
| rrpp | Oracle Reports Remote Printing Utility Data |
| rrq | SDLX Registration Request Data |
| rrr | Registry Mechanic Backup |
| rrr | Rhapzode Resource Repository |
| rrrx | Rhapzode Compiled Output |
| rrs4 | Remo Recover Recovery Session |
| rrt | Rhapzode Resource Template |
| rruff | RRUFF Database |
| rrw | Goldmine Report Writer Data |
| rrx | IBM Datacap Defines Data |
