| Extension |
File Type |
File Description |
| .r | Audio | Right Audio Channel File (Most common) |
| .r | Audio | Right Audio Channel File (Most common) |
| .r00 | Compressed | WinRAR Compressed Archive |
| .r01 | Compressed | WinRAR Split Archive Part 1 |
| .r02 | Compressed | WinRAR Split Archive Part 2 |
| .r03 | Compressed | WinRAR Split Archive Part 3 |
| .r1m | Audio | RealOne Streaming Media File |
| .ra | Audio | Real Audio File |
| .rad | Text | Radar ViewPoint Radar Data |
| .raf | Image | Fuji RAW Image File |
| .ral | Data | WinRail Track Design File |
| .ram | Audio | Real Audio Media |
| .rar | Compressed | WinRAR Compressed Archive |
| .ras | Raster Image | Sun Raster Graphic (Most common) |
| .ratdvd | Disk | RatDVD Disk Image |
| .raw | Image | Raw Image Data File (Most common) |
| .ray | Image | Rayshade Image |
| .rb | Developer | REALbasic Project (Most common) |
| .rbc | Backup | Retrospect Backup Catalog File (Most common) |
| .rbc | Backup | Retrospect Backup Catalog File (Most common) |
| .rbf | Backup | Retrospect Backup File (Most common) |
| .rbk | Backup | Windows 95 Registry Backup File |
| .rbp | Developer | REALbasic Project |
| .rbs | Audio | Rebirth Song File (Most common) |
| .rbt | Data | Lego MINDSTORMS NXT Program |
| .rbx | Executable | Rembo-C Compiled Script |
| .rbxl | Game | ROBLOX Location |
| .rbxm | Game | ROBLOX Model |
| .rc | Developer | Resource Script |
| .rcd | Data | Arcade File |
| .rcg | Data | Recog Character Recognition Set |
| .rcl | Disk | Easy CD and DVD Creator 6 Project |
| .rcproject | Video | iMovie '08 Project |
| .rdb | Data | N64 ROM Database (Most common) |
| .rdf | Settings | Resource Description Framework File (Most common) |
| .rdl | Vector Image | MicroStation Redline File |
| .rdo | Settings | Xerox Rawster Document Object File |
| .rdp | Settings | Remote Desktop Connection |
| .rds | Image | Ray Dream Studio Scene File |
| .rdx | Data | Reflex Data File |
| .readme | Text | Readme File |
| .rec | Video | Topfield PVR Recording |
| .reg | Settings | Registration Information File (Most common) |
| .rem | Misc | BlackBerry Encrypted Data File |
| .res | Developer | Windows Resource File (Most common) |
| .ret | Data | BusinessObjects Template |
| .rev | Compressed | RAR Recovery Volume Set |
| .rex | Audio | ReCycle Loop File |
| .rez | Plugin | Escape Velocity Plug-in File |
| .rf1 | Data | Retirement Forecast File |
| .rfa | Data | Revit Family File |
| .rfl | Audio | Reason ReFill Sound Bank |
| .rfm | Game | rFactor Modification File |
| .rft | Image | Revit Family Template File |
| .rgb | Raster Image | RGB Bitmap (Most common) |
| .rge | Data | Entourage File Archive |
| .rgn | Data | Garmin Regional Map File |
| .rgo | Data | RepliGo File |
| .rgp | Game | RealArcade Game Package |
| .rgs | Executable | Registry Script |
| .rhp | Plugin | Rhino Plug-in |
| .rhtml | Web | Ruby HTML Web Page |
| .ric | Raster Image | NXT Image File |
| .rif | Image | Raster Image File |
| .rix | Image | ColorRIX Bitmap Graphic |
| .rjs | Web | Ruby Javascript File (Most common) |
| .rk | Compressed | WinRK File Archive |
| .rkp | Game | Rockchip MP4 Player Game |
| .rle | Raster Image | Run Length Encoded Bitmap |
| .rm | Video | Real Media File |
| .rmf | Audio | Rich Music Format |
| .rmi | Audio | RMID MIDI File |
| .rmj | Audio | Real Media Jukebox Audio File |
| .rmm | Audio | RAM Meta File |
| .rmr | Misc | ResumeMaker File |
| .rmvb | Video | RealVideo Variable Bit Rate File |
| .rmx | Audio | RealJukebox Format |
| .rnc | Developer | RELAX NG Compact Syntax File (Most common) |
| .rnd | Misc | PGP Random Seed File (Most common) |
| .rng | Audio | Nokia Composer Ringtone (Most common) |
| .rnq | Data | Renque Model File |
| .rod | Data | Actuate Report Object Design File |
| .rog | Data | Roger 2 Input Data File |
| .roi | Data | Report Object Instance (Most common) |
| .rol | Audio | Ad Lib Synthesized Instrument |
| .rom | Game | N64 Game ROM File (Most common) |
| .roq | Video | Id Software Game Video |
| .rou | Data | Gerber Route File |
| .rov | Misc | Report Object Variable |
| .rox | Executable | Actuate Report Object Executable File |
| .rp | Video | RealPix Clip |
| .rp2 | Game | RetroPlatform Player Program Archive |
| .rpb | Settings | Radmin Phonebook File |
| .rpj | Executable | Real Pac Batch Job File |
| .rpk | Settings | RadLight Media Player Skin |
| .rpl | Game | Toribash Replay File |
| .rpm | Compressed | Red Hat Package Manager File (Most common) |
| .rps | Settings | 3ds Max Render Preset Settings |
| .rpt | Data | Crystal Reports File (Most common) |
| .rrr | Backup | Registry Mechanic Backup File (Most common) |
| .rrt | Data | Rhapzode Resource Template |
| .rsd | Data | RealSQLDatabase File |
| .rsdf | Encoded | RapidShare Download File |
| .rsn | Audio | Reason Project File |
| .rso | Audio | NXT Brick Audio File |
| .rsr | Raster Image | Poser Model Preview File |
| .rsrc | Developer | Macintosh Resource File |
| .rss | Web | Rich Site Summary |
| .rst | Text | reStructuredText File |
| .rsw | Data | R&R SQL Report Writer Report File |
| .rt | Text | RealText Streaming Text File |
| .rtd | Text | RagTime Document |
| .rte | Compressed | RTE Encoded File (Most common) |
| .rtf | Text | Rich Text Format File |
| .rtfd | Text | Rich Text Format Directory File |
| .rti | Audio | Real Tracker Instrument |
| .rtm | Audio | Real Tracker Module (Most common) |
| .rtp | Misc | TurboTax Update File |
| .rts | Video | RealPlayer Streaming Media (Most common) |
| .rtx | Text | Rich Text Document |
| .ru | Developer | JavaSoft JRE 1.3 Library |
| .rul | Developer | InstallShield Rules |
| .rum | Video | Bink Video Subtitle File |
| .run | Game | Rune Map File (Most common) |
| .rv | Video | Real Video File |
| .rvproj | Game | RPG Maker VX Project File |
| .rvt | Data | Revit Project File |
| .rwp | Web | RapidWeaver Package |
| .rxdata | Game | RMXP Data File |
| .rxe | Executable | Lego Mindstorms NXT Executable Program |
| .rz | Compressed | Rzip Compressed File |
| .rzb | Data | Red Zion Book File |
| .rzk | Text | File Crypt Password File (Most common) |
| .rzn | Text | Red Zion Notes File |
| .rzs | Compressed | Red Zion Security File |
| .rzx | Encoded | File Crypt Encrypted File |
