| .r | R Script Format |
| .r*ch | BBEdit |
| .r0 | WinRAR Compressed Archive Format |
| .r00 | WinRAR Compressed Archive Format |
| .r01 | Split Multi-volume RAR Compressed File Archive (part 3) |
| .r02 | Split Multi-volume RAR Compressed File Archive (part 4) |
| .r03 | Split Multi-volume RAR Compressed File Archive (part 5) |
| .r04 | Split Multi-volume RAR Compressed File Archive (part 6) |
| .r05 | Split Multi-volume RAR Compressed File Archive (part 7) |
| .r06 | Split Multi-volume RAR Compressed File Archive (part 8) |
| .r07 | Split Multi-volume RAR Compressed File Archive (part 9) |
| .r08 | Split Multi-volume RAR Compressed File Archive (part 10) |
| .r09 | Split Multi-volume RAR Compressed File Archive (part 11) |
| .r0f | RingCentral Fax Document |
| .r1 | WinRAR Multi-Volume Archive Part 1 |
| .r10 | Split Multi-volume RAR Compressed File Archive (part 12) |
| .r11 | Split Multi-volume RAR Compressed File Archive (part 13) |
| .r12 | Norton Ghost Rar |
| .r13 | Norton Ghost Rar |
| .r14 | Norton Ghost Rar |
| .r15 | Norton Ghost Rar |
| .r16 | Norton Ghost Rar |
| .r17 | Norton Ghost Rar |
| .r18 | Norton Ghost Rar |
| .r19 | Norton Ghost Rar |
| .r1m | RealOne Streaming Media Format |
| .r1w | Reflection Setting |
| .r2 | WinRAR Multi-Volume Archive Part 2 |
| .r20 | Norton Ghost Rar |
| .r21 | Split Multi-volume RAR Compressed File Archive (part 23) |
| .r22 | Norton Ghost Rar |
| .r23 | Norton Ghost Rar |
| .r24 | Norton Ghost Rar |
| .r25 | Norton Ghost Rar |
| .r26 | Norton Ghost Rar |
| .r27 | Norton Ghost Rar |
| .r28 | Split Multi-volume RAR Compressed File Archive (part 30) |
| .r29 | Split Multi-volume RAR Compressed File Archive (part 31) |
| .r2d | RISA-2D |
| .r2k | Repertoire 2000 Music Database |
| .r2w | Reflection Settings |
| .r30 | Split Multi-volume RAR Compressed File Archive (part 32) |
| .r31 | Split Multi-volume RAR Compressed File Archive (part 33) |
| .r32 | Split Multi-volume RAR Compressed File Archive (part 34) |
| .r33 | Split Multi-volume RAR Compressed File Archive (part 35) |
| .r34 | Split Multi-volume RAR Compressed File Archive (part 36) |
| .r35 | Split Multi-volume RAR Compressed File Archive (part 37) |
| .r36 | Split Multi-volume RAR Compressed File Archive (part 38) |
| .r37 | Split Multi-volume RAR Compressed File Archive (part 39) |
| .r38 | Split Multi-volume RAR Compressed File Archive (part 40) |
| .r39 | Split Multi-volume RAR Compressed File Archive (part 41) |
| .r3d | REDCODE Multimedia Format |
| .r3t | RealNetworks RealText |
| .r40 | Split Multi-volume RAR Compressed File Archive (part 42) |
| .r41 | Split Multi-volume RAR Compressed File Archive (part 43) |
| .r42 | Split Multi-volume RAR Compressed File Archive (part 44) |
| .r43 | Split Multi-volume RAR Compressed File Archive (part 45) |
| .r44 | Split Multi-volume RAR Compressed File Archive (part 46) |
| .r45 | Split Multi-volume RAR Compressed File Archive (part 47) |
| .r46 | Split Multi-volume RAR Compressed File Archive (part 48) |
| .r47 | Split Multi-volume RAR Compressed File Archive (part 49) |
| .r48 | Split Multi-volume RAR Compressed File Archive (part 50) |
| .r49 | Split Multi-volume RAR Compressed File Archive (part 51) |
| .r50 | Split Multi-volume RAR Compressed File Archive (part 52) |
| .r51 | RAR Compressed Files From A Multi-volume Archive |
| .r52 | RAR Compressed Files From A Multi-volume Archive |
| .r53 | RAR Compressed Files From A Multi-volume Archive |
| .r54 | RAR Compressed Files From A Multi-volume Archive |
| .r55 | RAR Compressed Files From A Multi-volume Archive |
| .r56 | RAR Compressed Files From A Multi-volume Archive |
| .r57 | RAR Compressed Files From A Multi-volume Archive |
| .r58 | RAR Compressed Files From A Multi-volume Archive |
| .r59 | RAR Compressed Files From A Multi-volume Archive |
| .r60 | RAR Compressed Files From A Multi-volume Archive |
| .r61 | RAR Compressed Files From A Multi-volume Archive |
| .r62 | RAR Compressed Files From A Multi-volume Archive |
| .r63 | RAR Compressed Files From A Multi-volume Archive |
| .r64 | RAR Compressed Files From A Multi-volume Archive |
| .r65 | RAR Compressed Files From A Multi-volume Archive |
| .r66 | RAR Compressed Files From A Multi-volume Archive |
| .r67 | RAR Compressed Files From A Multi-volume Archive |
| .r68 | RAR Compressed Files From A Multi-volume Archive |
| .r69 | RAR Compressed Files From A Multi-volume Archive |
| .r70 | RAR Compressed Files From A Multi-volume Archive |
| .r71 | RAR Compressed Files From A Multi-volume Archive |
| .r72 | RAR Compressed Files From A Multi-volume Archive |
| .r73 | RAR Compressed Files From A Multi-volume Archive |
| .r74 | RAR Compressed Files From A Multi-volume Archive |
| .r75 | RAR Compressed Files From A Multi-volume Archive |
| .r76 | RAR Compressed Files From A Multi-volume Archive |
| .r77 | RAR Compressed Files From A Multi-volume Archive |
| .r78 | RAR Compressed Files From A Multi-volume Archive |
| .r79 | RAR Compressed Files From A Multi-volume Archive |
| .r8 | Microsoft Flight Simulator Texture |
| .r80 | RAR Compressed Files From A Multi-volume Archive |
| .r81 | RAR Compressed Files From A Multi-volume Archive |
| .r82 | RAR Compressed Files From A Multi-volume Archive |
| .r83 | RAR Compressed Files From A Multi-volume Archive |
| .r84 | RAR Compressed Files From A Multi-volume Archive |
| .r85 | RAR Compressed Files From A Multi-volume Archive |
| .r86 | RAR Compressed Files From A Multi-volume Archive |
| .r87 | RAR Compressed Files From A Multi-volume Archive |
| .r88 | RAR Compressed Files From A Multi-volume Archive |
| .r89 | RAR Compressed Files From A Multi-volume Archive |
| .r8? | Microsoft Word For DOS Font |
| .r90 | RAR Compressed Files From A Multi-volume Archive |
| .r91 | RAR Compressed Files From A Multi-volume Archive |
| .r92 | RAR Compressed Files From A Multi-volume Archive |
| .r93 | RAR Compressed Files From A Multi-volume Archive |
| .r94 | RAR Compressed Files From A Multi-volume Archive |
| .r95 | RAR Compressed Files From A Multi-volume Archive |
| .r96 | RAR Compressed Files From A Multi-volume Archive |
| .r97 | RAR Compressed Files From A Multi-volume Archive |
| .r98 | RAR Compressed Files From A Multi-volume Archive |
| .r99 | RAR Compressed Files From A Multi-volume Archive |
| .ra | RealAudio Audio Format |
| .ra2 | Flare RAW |
| .RA3Autosave | Command & Conquer Red Alert 3 Save Game |
| .RA3Campaign | Command & Conquer Red Alert 3 Save Game |
| .ra3replay | Command & Conquer: Red Alert 3 Replay |
| .ra3skirmish | Command & Conquer: Red Alert 3 Skirmish Map |
| .rac | Venue Race Application |
| .rad | Reality AdLib Tracker 2 Format |
| .radiumkey2 | Radium Registration Format |
| .radius | Ruby-Radius Scipt |
| .radq | Need For Madness Game Archive |
| .rae | TrueZIP Encrypted ZIP Archive |
| .raes | TrueZIP Encrypted ZIP Archive |
| .raf | Fuji CCD-RAW Graphic Format |
| .rag | RAM Advanse Generator |
| .rai | SPEFO |
| .rake | Ruby Makefile |
| .rakefile | Ruby Makefile |
| .ral | WinRail Track Design Format |
| .ram | Real Audio Metafile |
| .ramd | Repeat After Me Document |
| .ran | Dexterpen |
| .rap | Magix Music Studio Rap |
| .rapc | Java 2 ME Unit |
| .rar | WinRAR Compressed Archive Format |
| .rar1 | RAR Archive |
| .rar5 | WinRAR Compressed Archive Format |
| .rarenx | Egis Encrypted RAR |
| .rarx | Renamed RAR |
| .ras | Sun Raster Bitmap Format |
| .raskinlicense | Raskin For Mac License Format |
| .raskinplace | Raskin Place Settings Format |
| .rast | Sun Raster Bitmap Image |
| .rat | PICS Platform For Internet Content Selection Format |
| .ratdvd | RatDVD Commpressed DVD Movie |
| .rav | FIFA 2001 Data Environment Format |
| .raw | Digital Camera Photo RAW Image Format |
| .rax | RealMedia Streaming Format |
| .ray | Rayshade Picture Image Format |
| .ra_ | Resco Photo Viewer Thumbnail Cache |
| .rb | Ruby Script Format |
| .rb0 | Trend AntiVirus Backup |
| .rb1 | R:Base Data Format |
| .rb2 | R:Base Data Format |
| .rb3 | R:BASE Data |
| .rb4 | Trend AntiVirus Backup Format |
| .rba | RegexBuddy Regular Expression |
| .rbb | Top Secret Crypto Gold Random Bits Bin |
| .rbc | Easy Resume Creator Pro Resume Format |
| .rbdf | Reading For The Blind And Dyslexic Audio Book With Text |
| .rbf | Microsoft Windows Rollback Script Format |
| .rbg | RegexBuddy GREP Action |
| .rbi | EBahn Reader |
| .rbj | Extra Redcode Kit Compiled Redcode Object Format |
| .rbk | Microsoft Windows 95 Registry Backup Format |
| .rbl | RegexBuddy Library |
| .rbm | Propellerhead ReBirth Modulation V2.0 |
| .rbo | REALbasic Class |
| .rbp | REALbasic Project Format |
| .rbs | Rebirth Song Format |
| .rbt | Lego MINDSTORMS NXT Program Format |
| .rbtx | NXT Create Pack & Go Package |
| .rbvcp | Real Studio Project Format |
| .rbw | Ruby |
| .rbx | IBM Rembo-C Compiled Script Format |
| .rbxl | ROBLOX Game Format |
| .rbxm | ROBLOX Model Format |
| .rbxs | ROBLOX Script |
| .rbz | Rail Baron Player Saved Game Format |
| .rc | Microsoft Visual Studio Visual C/C++ Resource Script Format |
| .rc1 | Samsung S5230 Firmware Format |
| .rc2 | Microsoft Visual Studio Visual C/C++ Non-compilable Resource Script Format |
| .rc3 | Visual C Resource |
| .rcb | Ripple Chat Bot Document |
| .rcd | PcAnywhere Recorded Session Format |
| .rcf | Prototype Game Format |
| .rcg | Netscape Newsgroup Format |
| .rch | SWAT Reach Output |
| .rcl | Easy CD And DVD Creator Project Format |
| .rcn | QRacing Track |
| .rco | Sony PlayStation Portable PSP Resource Format |
| .rcp | Rich Chart Builder Project |
| .rcproject | Apple IMovie Project Format |
| .rcs | RandomControl Scene Format |
| .rct | Microsoft Visual Studio Resource Template Format |
| .rcu | RealWorld Layered Cursor Image |
| .rcv | Eudora Temporary Download |
| .rcx | REDCINE-X Project Format |
| .rcy | ReCycle Audio Loop Format |
| .rd | R Document |
| .rd2 | TOCA Race Driver 2 Saved Game |
| .rd3 | CorelDRAW CorelDream 3D |
| .rd3f | CorelDRAW CorelDream 3D |
| .rd5 | Autodesk Road Aligment |
| .rda | Oracle Storage Area Format |
| .rdat | RNA Data (RDAT) |
| .rdata | R Workspace Format |
| .rdb | N64 Nintendo 64 ROM Database Format |
| .rdc | IDRISI Raster Documentation Format |
| .rdd | ALTA |
| .rde | Painkiller Overdose Game |
| .rdf | Resource Description Framework RSS Feed Format |
| .rdg | Morae Recorded Video |
| .rdi | Device Independent Bitmap Format |
| .rdl | Corel Paradox Format |
| .rdlc | Microsoft Visual Studio Report Definition Format |
| .rdlx | Microsoft Power View Project Format |
| .rdm | Ragdoll Masters Preference |
| .rdo | Xerox Rawster Document Object Format |
| .rdoc | RubyDoc Script |
| .rdp | Microsoft Windows Remote Desktop Connection Settings Format |
| .rds | Ray Dream 3D Animation Format |
| .rdt | Adobe Captivate RoboDemo Template |
| .rdv | NTgraph |
| .rdw | Real-DRAW Project |
| .rdx | Borland Reflex Database Format |
| .rdy | INet-Server |
| .rdz | Mandrake Linux Install |
| .re | Python Regular Expressions Source Code |
| .re2 | NEK5000 Mesh |
| .re4 | Resident Evil 4 |
| .rea | Readme Text |
| .readme | Visual FoxPro Documenting Wizard List |
| .real | Gnome Desktop |
| .reapeaks | REAPER Scratch |
| .reb | REBOL Script Format |
| .rec | Recorded Format |
| .reco | Evernote |
| .record | Recorded Audio Format |
| .red | CADViewer Redline Markup Format |
| .redir | Spotify Redirect Format |
| .ref | Reference Format |
| .reference | Budget In Brief Application Reference Format |
| .refi | E-Sword Reference IOS Notes |
| .refresh | Microsoft Visual Studio Refresh Format |
| .refx | E-Sword Reference Library Note |
| .reg | Windows Registry Data Format |
| .regi | Kagi Registration Module |
| .regs | Netscape Registry |
| .regtrans-ms | Microsoft Windows Vista And Windows 7 Registry Format |
| .regularizer | SAM Transition Regularizer |
| .rej | Mercurial Reject |
| .rel | Norton Internet Security 2001 Log Format |
| .reloc | Microsoft Windows EXE Relocation Format |
| .rels | Microsoft Open Office XML Relationships Format |
| .rem | BlackBerry Encrypted Data Format |
| .renderman | Pixar RenderMan 3.1 Specification |
| .rep | BusinessObjects Report Format |
| .repatch | Reason DCAM EnvShaper Effect Preset |
| .repx | XtraReports Report Definition |
| .req | SSL Certificate Request Format |
| .res | Microsoft C, C++ Compiled Resource Format |
| .resdex | Stronghold 3 Resource |
| .resjson | Microsoft Windows 8 Metro JavaScript Format |
| .resmoncfg | Microsoft Windows Resource Monitor Settings Format |
| .resourceconfig | Visual Studio Resource Configuration |
| .resources | Microsoft Visual Studio Resource Format |
| .resp | Microsoft Windows Report Log |
| .rest | ReStructuredText |
| .resw | Microsoft Windows 8 Resources Format |
| .resx | Microsoft Visual Studio .NET XML Resource Template Format |
| .ret | RETScreen Project Format |
| .rev | WinRAR Recovery Volume Format |
| .rew | MRMC Markov Reward Model Checker Definition |
| .rewi | MRMC Markov Reward Model Checker Definition |
| .rex | ReCycle Audio Loop Export Format |
| .rez | LithTech Game Engine Resource Format |
| .rf | Sun Bitmap Image |
| .rf0 | SmartWare Runtime Project |
| .rf1 | Retirement Forecast Format |
| .rf2 | SmartWare Runtime Project |
| .rf3 | SmartWare Runtime Project |
| .rf4 | SmartWare Runtime Project |
| .rf5 | Tektronix |
| .rfa | Autodesk Revit Architecture Family Format |
| .rfb | RoboForm Bookmarks Format |
| .rfc | RoboForm Contact Format |
| .rfd | RecogniFORM Form Definition Format |
| .rfe | RockFlow Log |
| .rfg | RFG Integrator System Database |
| .rfgs_pc | Red Faction: Guerilla Saved Game Format |
| .rfh | RFG Integrator Householding Database |
| .rfi | SPEFO Stellar Spectra Analysis |
| .rfl | ANSYS Format |
| .rfm | RFactor Modification Format |
| .rfmod | RFactor 2 Mod |
| .rfn | RoboForm SafeNote Files |
| .rfo | RoboForm License And Options Format |
| .rfp | RoboForm Passcard Format |
| .rfq | RoboForm SearchCard Format |
| .rfr | Adobe Photoshop Frame Filter |
| .rfs | RealFlow Script |
| .rft | Revit Template Format |
| .rfv | Restricted Focus Viewer Input |
| .rfw | Rockchip Firmware Format |
| .rfx | RoboForm Blocked Passcard |
| .rg | Rosegarden Music |
| .rgb | SGI RGB Bitmap Format |
| .rgba | Silicon Graphics Image File Format |
| .rgbe | Radiance Map |
| .rgd | Rosegarden Device Definition |
| .rgdb | Adobe Registration Database |
| .rge | Microsoft Outlook For Mac Archive Format, Entourage Personal Folder Format |
| .rgf | Advanced Registry Tracer Scan Data |
| .rgh | ZZ RouGH Image |
| .rgi | RealArcade Game Installer |
| .rgm | Essence Game Engine Model |
| .rgmb | RootsMagic Backup Format |
| .rgmc | RootsMagic Genealogy Project Format |
| .rgn | Garmin Region Format |
| .rgo | RepliGo Virtual Print Format |
| .rgp | RealArcade Game Package |
| .rgrp | Pro Tools Region Group Format |
| .rgs | InstallShield Script For Windows Registry |
| .rgss2a | RPG Maker VX RGSS Encrypted Archive Format |
| .rgss3a | RPG Maker VX RGSS Version 3 Encrypted Archive |
| .rgssad | RPG Maker VX RGSS Encrypted Archive |
| .rgu | Microsoft Windows Mobile Registry Entry |
| .rguninst | RealArcade Uninstall Script |
| .rgz | Ragnarok EXE And BGM Patch Archive |
| .rh | C++ Resource Header |
| .rha | Adobe RoboHelp AIR Help Project |
| .rhistory | R History Format |
| .rhk | Backdoor.Win32.Rbot.rhk Trojan Virus |
| .rhl | EdgeSounds RatHole Compressed Audio |
| .rhm | Right Hemisphere Material |
| .rhp | Encore Format Format Format |
| .rhtml | Ruby HTML Web Page Format |
| .ri | Lotus 1-2-3 Data |
| .ribbons | Ribbons |
| .ric | Lego NXT Image Format |
| .rid | GerbMagic Raster Image |
| .rif | Corel Painter Raster Image Format |
| .riff | Painter Raster Image |
| .rig | LightWave 3D RIG Function Format |
| .rik | SharpMap |
| .rim | BioWare Resource Image Format |
| .rio | IBM AIX System |
| .rip | Lotus Notes Error |
| .ripxr | RipXR Compressed Archive |
| .ris | Research Information Systems Citation Format |
| .riscos | Acorn RISC OS |
| .rise | RISE Information Model Format |
| .riv | CRiSP Harvest |
| .rix | ColoRix Bitmap Image |
| .rjs | RealJukebox Skin |
| .rjt | RealPlayer Track Info Style |
| .rk | WinRK Archive Format |
| .rkc | Mario Kart Wii Competition Data |
| .rkg | Mario Kart Wii Ghost Data |
| .rkp | Rockchip MP4 Player Game |
| .rkr | Rakarrack |
| .rkt | Racket Information Module |
| .rkv | Star Wars The Clone Wars Republic Heroes Game Archive |
| .rkw | RockWorks Graphics |
| .rl | R.viewer Format |
| .rl1 | Descent 1 Registered Level |
| .rl2 | Descent 2 Registered Level |
| .rl4 | Device-independent Bitmap |
| .rla | Alias/Wavefront Bitmap Image |
| .rlb | Alias/Wavefront Bitmap Image |
| .rlc | ArcView Image |
| .rld | Norton Commander Temporary |
| .rle | Run Length Encoded Bitmap |
| .rle.gz | Golly Compressed Pattern Format |
| .rlf | ArcGIS Report Layout Format |
| .rlg | Weibull++ |
| .rli | RealWorld Graphics Layered Image |
| .rll | Resource Hacker Resource Library Format |
| .rln | Alpha Four Database |
| .rlog | MPICH Log |
| .rls | RadLight Skin Format |
| .rlst | Sims 3 Data |
| .rlt | ReliaSoft BlockSim & Weibull++ |
| .rlw | Ricochet Lost Worlds: Recharged |
| .rlx | XMetaL Compiled Form |
| .rm | RealMedia Format |
| .rm3d | RiskMetrics RiskManager |
| .rma | RealMedia Audio |
| .rman | Oracle Datafile Backup |
| .rmap | CompeGPS Land Raster Map |
| .rmb | SafeGuard RemovableMedia Keyring Backup |
| .rmbak | Registry Mechanic Backup Format |
| .rmc | RMCalc |
| .rmd | Microsoft RegMaid Document Format |
| .rmdp | Alan Wake Game Data |
| .rme | Final Fantasy Audio |
| .rmf | Adobe Acrobat Rights Management Document Format |
| .rmg | Rimage Image |
| .rmgc | RootsMagic Genealogy Database |
| .rmi | MIDI-sequention Music (RIFF RMID Format) |
| .rmid | RIFF RMID Midi Format |
| .rmj | RealAudio Media Format |
| .rmk | CA Clipper RMake Makefile |
| .rml | Redline Markup Language Format |
| .rmm | RAM Meta Format |
| .rmn | Oracle Recovery Manager Script |
| .rmp | RealAudio Audio Format |
| .rmr | ResumeMaker Format |
| .rms | RealMedia Secure Media File Format |
| .rmskin | Rainmeter Skin Format |
| .rmt | Linksys Router Firmware Format |
| .rmuf | Alpha Five Runtime Format |
| .rmv | The Simpsons Hit & Run Video Format |
| .rmvb | RealMedia Variable Bitrate Format |
| .rmw | RAM Commander Database |
| .rmx | RealMedia Secure Media Clip |
| .rna | Malware |
| .rnc | RNC ProPack Archive Format |
| .rnd | AutoCAD Autoshade Rendering Slide Format |
| .rng | Random Number Generator Data Format |
| .rnk | Dial-up Shortcut |
| .rnl | GTX Runlength Encoded Bitmap Graphics |
| .rnq | Renque Model Format |
| .rnr | The 11th Hour Game Data |
| .rns | Reason Audio Format |
| .rnt | EdgeCAM Licensing Data |
| .rnw | Sweave Source |
| .rnx | RealPlayer Audio Or Settings Format |
| .ro | ROwin Project |
| .roacj | Call Of Juarez Game Resource Data |
| .rob | Wintask Compiled Program |
| .robo | RoboMind Source Code |
| .roc | SpaceCAD Rocket Design |
| .roca | RIB Office Compressed Archive Format |
| .rock | Rockbox Installation Format |
| .rockwell | Rockwell (modem) |
| .rockwell-2 | Rockwell 2-bit ADPCM Data |
| .rockwell-3 | Rockwell 3-bit ADPCM Data |
| .rockwell-4 | Rockwell 4-bit ADPCM Data |
| .rod | Actuate E.Report Designer Report Object Design |
| .rodl | RemObjects Definition Language Format |
| .roff | Unformatted Manual Page (Roff/nroff/troff/groff) |
| .rofl | Leagues Of Legends Replay |
| .rog | Roger 2 Data Format |
| .roh | Avantes |
| .roi | Report Object Instance |
| .rol | AdLib Visual Composer Music Data Format |
| .rom | Read Only Memory Image (emulators/AONs) |
| .roo | WinRAR Archive |
| .roq | Id Software Game Video |
| .ros | Dynamite VSP Rail Object Style Format |
| .rot | Homeworld 2 Game Graphics Data Format |
| .rotest | RemObjects SDK Test Format |
| .rotestresult | RemObjects SDK Test Results Format |
| .rou | Gerber Route Format |
| .rov | Actuate E.Report Designer Report Object Value |
| .row | Actuate E.Report HTML Report Document |
| .rox | Actuate E.Report Designer Report Object Executable Format |
| .roxio | Roxio Creator Project Format |
| .roz | ASc TimeTables Timetable |
| .rp | Axure RP Project Format |
| .rp2 | RetroPlatform Player (Amiga Forever) Format |
| .rp3 | Need For Speed Game |
| .rp9 | RetroPlatform Format |
| .rpa | RIB ITWO Project Archive Format |
| .rpack | Call Of Juarez Game Data |
| .rpb | Radmin Phonebook Format |
| .rpbm | Portable Bitmap Image |
| .rpc | Visual Basic Crystal Reports |
| .rpd | Roleplay Designer Data Format |
| .rpe | Performance Analyzer |
| .rpf | 3ds Max Rich Pixel Format |
| .rpg | The RPG Programming Language |
| .rpgm | Portable Greyscale Image |
| .rpi | Render Extension |
| .rpj | RealPlayer JavaScript Format |
| .rpk | NeverForget Backup Reminder Format |
| .rpl | Toribash Replay Game Format |
| .rplib | Axure Widget Library Format |
| .rpln | Adobe InDesign Required Function Library |
| .rpm | Linux Package Manager Format |
| .rpmsg | Microsoft Restricted Permission Message Format |
| .rpn | ACT! 2.0 Report |
| .rpnm | Portable Image Image |
| .rpo | IBM XL C/C++ For Linux Compiler |
| .rpp | REAPER Project Format |
| .rppm | Portable Image Image Format |
| .rpprj | Axure RP Shared Project Format |
| .rpr | IBM Voice Type Languages Vocabels |
| .rprofile | Quick-R R Programming Language Configuration |
| .rps | 3D Studio Max Render Preset Settings Format |
| .rpt | Report Format |
| .rpt2 | ESignal Report |
| .rptproj | Microsoft Visual Studio 2008 Report Project |
| .rptr | RafflePrinter Document Format |
| .rptx | Spiceworks Report |
| .rpv | RealPlayer Visualization |
| .rpw | RPWiz Project |
| .rpx | Repute Tutorial |
| .rpy | Python Script Format |
| .rpym | RenPy Module |
| .rpz | Crystal Reports ZIP Compressed And Encrypted Report |
| .rqc | Micro Focus Revolve |
| .rqi | TrueNet R-Quest Disc Image |
| .rqm | IBM RequisitePro Metrics Report |
| .rqt | Report Quality Plotting Module |
| .rqy | Microsoft Excel OLE DB Query |
| .rra | Windows Installer Temporary Format Format |
| .rrc | BlackBerry Java Resource Content |
| .rrd | Reduced Resolution Dataset Format |
| .rrd4j | RRD4J Graph |
| .rrf | Raytech |
| .rrg | JRiver Media Center License |
| .rrh | BlackBerry Resource Header |
| .rri | RealWorld Icon Editor Picture Image Format |
| .rrpa | Oracle Reports Remote Printing Utility PDF Report |
| .rrr | Registry Mechanic Backup Format |
| .rrt | Rhapzode Resource Template Format |
| .rrx | IBM Datacap Define |
| .rs | Sun Raster Bitmap Image Format |
| .rs1 | RETScreen Spreadsheet |
| .rs2 | RailSim2 Layout Format |
| .rs7 | LightTools Radiant Source Model |
| .rs8 | ProSource |
| .rsa | RSA Digital Certificate Format |
| .rsb | Red Storm Bitmap Format |
| .rsc | Resource Format |
| .rsd | Database Format |
| .rsd-journal | REALSQLDatabase Journal |
| .rsdb | Resort Software Database |
| .rsdf | RapidShare Download Settings Format |
| .rsds | SharePoint Shared Data Source |
| .rsed | ResEdit |
| .rsf | Mediafour MacDrive Macintosh Resource Fork |
| .rsfx | Reflection |
| .rsg | Drakan Order Of The Flame |
| .rsh | Warhammer 40,000 Texture |
| .rsi | Reactis |
| .rsl | Robot Scripting Language |
| .rsm | ReliaSoft MPC 3 Format |
| .rsml | RealPlayer ML |
| .rsn | Propellerhead Reason Audio Format |
| .rso | LEGO NXT Brick Audio Format |
| .rsp | Linker Response Format |
| .rsq | IBM 4690 Operating System |
| .rsr | Poser Model Preview Format |
| .rsrc | MAC OS Resource Format |
| .rsrs | Buddy API |
| .rss | Really Simple Syndication - RSS File Format |
| .rst | ReStructuredText Format |
| .rsu | Reflection For IBM Updated Settings |
| .rsv | RSView32 Project Format |
| .rsw | R&R SQL Report Writer Report Format |
| .rsx | RED Metadata XML Format |
| .rsym | ArchiCAD For MAC Geometric Description Language |
| .rs_ | Macintosh Resource Fork |
| .rt | RealText Subtitle Format |
| .rt2 | OziExplorerCE Route |
| .rta | IBM Voice Type Languages Vocabulary Format |
| .rtab | Randy Tab Guitar Tablature |
| .rtb | Rhino 3D Toolbar Collection |
| .rtc | AutoCAD Civil Rating Curve Data Format |
| .rtd | Retina Network Security Scanner Output Format |
| .rte | OziExplorer Route Format |
| .rtf | Rich Text Format Document |
| .rtfd | Rich Text With Graphic Document Format |
| .rtg | Autodesk Maya 3D Scene Data |
| .rth | ANSYS Results |
| .rti | Real Tracker Instrument Format |
| .rtk | Adobe RoboHelp Configuration |
| .rtkt | Royaltek Binary Data |
| .rtl | Text |
| .rtm | Real Tracker Music Module (MOD) Format |
| .rtmap | CompeGPS Land Raster Map |
| .rtn | MeasureMind 3D |
| .rtp | Microsoft Software Update Format |
| .rtpi | 3rdTech Scanner |
| .rtr | Astrotite 200X Offline Data Repair |
| .rts | Resource Tuner Console Script Format |
| .rtsl | RealAudio RTSL Document |
| .rtsp | Apple QuickTime Real-time Streaming Protocol |
| .rtstn | Audials Station Format |
| .rtsx | Royal TS Document Settings |
| .rtt | Ragtime |
| .rtttl | RTTTL / Nokring Mobile Ring-tone Format |
| .rtu | RivaTuner Update |
| .rtw | Real-Time Workshop Database |
| .rtwsh | Radiotracker Wishlist Format |
| .rtx | Mobile Phone Ringtone |
| .rt_ | Microsoft Windows Winhelp Compressed |
| .ru | Russian Text Or Localization Format |
| .rub | JQuery Rules |
| .ruf | ProWORX Tables Reference Format |
| .ruj | Oracle Recovery-Unit Journal |
| .rul | Rule Format |
| .rule | Visual C++ Project Rules |
| .ruleset | Microsoft Visual Studio Code Analysis Ruleset Format |
| .rum | Bink Video Subtitle Format |
| .run | Linux Executable Format |
| .rup | IBM Rational Unified Process |
| .rus | Navitel Navigator Map |
| .rv | RealVideo Video Format |
| .rv3 | Newsbin Pro |
| .rv9 | RealVideo Movie |
| .rvb | Rhinoceros 3D Visual Basic Script |
| .rvc | TNTmips Windows Version Project |
| .rvd | VPHybridCAD Native Drawing Format |
| .rvdata | RPG Maker Data Format |
| .rvdata2 | RPG Maker VX Data |
| .rvf | RichView Document |
| .rvg | Revit External Group |
| .rvi | Revenant Game Archive |
| .rvid | Snapz Pro X Video Format |
| .rvl | Muvee Project |
| .rvm | Revenant Game Archive |
| .rvmat | Armed Assault Texture |
| .rvp | Microsoft Scan Configuration |
| .rvproj | RPG Maker VX Project Format |
| .rvproj2 | RPG Maker VX Project |
| .rvr | Revenant Game Archive |
| .rvs | Revenant Game Archive |
| .rvt | Autodesk Revit Architecture Project Format |
| .rvw | ReviewMate Review |
| .rvx | Real Protected Video Format |
| .rw | Navicat For MySQL |
| .rw2 | Panasonic Lumix RAW Image Format |
| .rw3 | RapidWeaver Site Design Format |
| .rw5 | Survey Pro Data |
| .rwa | Weibull++ |
| .rwc | WAsP Regional Wind Climate |
| .rwd | RWD Compressed Game Archive |
| .rwg | Random Word Generator File Format |
| .rwk | Bentley InRoads Project |
| .rwl | D-Lux 4 RAW Image Format |
| .rwlibrary | Paperless Receipt Library Format |
| .rwm | Windows Imaging Resource Only |
| .rwo | Matlab Output |
| .rwp | RapidWeaver Web Package Format |
| .rwplugin | RapidWeaver Plugin Format |
| .rwr | RiffWorks IntelliRiffer |
| .rws | Borland C++ Resource Workshop Symbol Format |
| .rwsnippet | RapidWeaver Snippet Format |
| .rwstyle | RapidWeaver Style Format |
| .rwsw | RapidWeaver Website Saved Project |
| .rwtheme | RapidWeaver Theme Format |
| .rwtl | HyperRESEARCH |
| .rwx | Netscape Live 3D |
| .rwz | Microsoft Outlook Internet Rules Settings Format |
| .rx | MS-DOS 7 |
| .rx2 | ReCycle! Audio Loop Format |
| .rx3 | FIFA 11 Texture |
| .rxc | Roxio Certificate Format |
| .rxd | Attachmate Reflection X Manager Definition |
| .rxdata | RPG Maker RMXP Data Format |
| .rxe | Lego Mindstorms NXT Executable Format |
| .rxl | Seetrax Ranger CAD Drawing |
| .rxm | Reflection X Multi Session |
| .rxml | Roxen Macro Language |
| .rxp | Easy CD & DVD Creator 6 Playlist |
| .rxproj | RPG Maker Project |
| .rxs | RSIGuard RSIScript |
| .rxx | RAR Compressed Files From A Multi-volume Archive |
| .rz | Rzip Compressed Archive |
| .rzb | Red Zion E-book Book Format |
| .rzk | File Crypt Password Format |
| .rzn | Red Zion E-book Notes Format |
| .rzr | Renamed WinRAR Archive |
| .rzs | Red Zion Security Format |
| .rzx | File Crypt Encrypted Format |
