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file extension Windows/OS2/Apple/Unix/Dos

File ExtensionsWindows/OS2/Apple/UNIX

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R = Fortran preprocessor Source RatFor

R = Macintosh Resource similar to RC

R = Paradox file

R = Pegasus Mail resource

R#+A = (MAC FILE TYPE) RagTime Classic text file

R#+D = (MAC CREATOR CODE) Rag Time 3

R*ch = (MAC FILE_TYPE) BBEdit

R00 = Norton Ghost rar file

R01 = Norton Ghost rar file

R01 = RAR compressed files from a multi-volume archive

R02 = Norton Ghost rar file

R02 = RAR compressed files from a multi-volume archive

R03 = Norton Ghost rar file

R04 = Norton Ghost rar file

R05 = Norton Ghost rar file

R06 = Norton Ghost rar file

R07 = Norton Ghost rar file

R08 = Norton Ghost rar file

R09 = Norton Ghost rar file

R0C = Fax cover

R0F = Fax document

R0H = Fax header

R10 = Norton Ghost rar file

R11 = Norton Ghost rar file

R12 = Norton Ghost rar file

R13 = Norton Ghost rar file

R14 = Norton Ghost rar file

R15 = Norton Ghost rar file

R16 = Norton Ghost rar file

R17 = Norton Ghost rar file

R18 = Norton Ghost rar file

R19 = Norton Ghost rar file

R20 = Norton Ghost rar file

R21 = Norton Ghost rar file

R22 = Norton Ghost rar file

R23 = Norton Ghost rar file

R24 = Norton Ghost rar file

R25 = Norton Ghost rar file

R26 = Norton Ghost rar file

R27 = Norton Ghost rar file

R28 = Norton Ghost rar file

R29 = WinRAR open with: "%ProgramFiles%\winrar\WinRAR.exe" "%1"

R29 = WinRAR open with: "%ProgramFiles%\WinRAR\WinRAR.exe" "%1"

R29 = WinRAR open with: "%ProgramFiles%\xp\WinRAR\WinRAR.exe" "%1"

R2D = Reflex 2 Data

R2LANG = Rainlendar2Lang open with: %Root%\Tools\Rainlendar2\Rainlendar2.exe -i "%1"

R2LIC = Rainlendar2License open with: %Root%\Tools\Rainlendar2\Rainlendar2.exe -i "%1"

R2SKIN = Rainlendar2Skin open with: %Root%\Tools\Rainlendar2\Rainlendar2.exe -i "%1"

R2SKIN-ADDON = Rainlendar2SkinAddon open with: %Root%\Tools\Rainlendar2\Rainlendar2.exe -i "%1"

R2V3 = (MAC FILE_TYPE) Streamline

R3T = Mime: text/vnd.rn-realtext3d

R8 = Raw graphics (one byte per pixel) plane one (PicLab)

R8 = Red channel image data (24bit 3D animation) (Cubicomp PictureMaker)

R81 = Game: Ms flight Texture file

R82 = Game: Ms flight Texture file

R8? = Microsoft Word for DOS/WordPerfect Font

R8L = LaserJet Landscape Font

R8P = Intellifont Pcl 4 bitmap font file

R?? = RAR Compressed File (?? can be 01 to 99)

RA = Mime: application/x-pn-realaudio

RA = Mime: audio/vnd.rn-realaudio

RA = Mime: audio/x-pn-realaudio

RA = Mime: audio/x-pn-realaudio-plugin

RA = Mime: audio/x-realaudio

RA = RealAudio

RA = Remote Access data file

RAC = Subtitling file format

RAD = Radiance image file

RAD = Reality AdLib Tracker 2-op FM music

RAF = Illum src Rk file

RAM = Mime: application/x-pn-realaudio

RAM = Mime: audio/x-pn-realaudio

RAM = Mime: audio/x-pn-realaudio-plugin

RAM = Real Audio sound

RAM = RealMedia

RAO = ReadAllOver (YOUniverse)

RAP = Magix Musstu Rap file

RAR = Mime: application/rar

RAR = RAR-compressed archive

RAS = Mime: application/x-cmu-raster

RAS = Mime: image/cmu-raster

RAS = Mime: image/x-cmu-raster

RAS = Sun Raster bitmap image, UNIX

RAST = Mime: image/cmu-raster

RAST = Sun Raster bitmap image, UNIX

RAT = "Recreational Software Advisory Council" (RSACI.RAT)

RAT = RATS datafile

RAV = Game: fifa 2001 data enviro file

RAW = Bitmap picture

RAW = HSI Raw image format

RAW = PCM Signed Raw Sound File

RAW = Raw File Format (bitmap)

RAW = RAW grayscale/24-bit RGB bitmap image

RAW = RAW sound file

RAW = RealAudio sound; see RA

RAX = Image File

RAY = Rayshade

RB = (fuzzy rule based definition)see below

RB = Mime: application/x-rocketbook

RB1 = R:Base Data File

RB2 = R:Base Data File

RB3 = R:Base Data File

RBD = (fuzzy rule based definition)fuzzy system modelling environment in ebnf-notation

RBF = Rbase datafile

RBH = RoboHelp Configuration

RBI = Adressmn file

RBM = Propellerhead ReBirth Modulation v2.0

RBS = RealiMation 3D Object

RC = Emacs configuration record

RC = ResourCe Script "Borland C++"

RC = ResourCe Script "Ms C, C++"

RC = ResourCe Script "Resource WorkShop"

RC2 = Ms Developer Studio not editable resources

RC3 = Vc98 resources file

RC_ = Winhelp file (compressed)

RCD = Formula 1 car race 2001 Season01 Drivers file

RCE = Ntgraph Gui Ctl3d file

RCF = "Audiogalaxy Rhapsody" storage file

RCF = Game: colin Mc Rae car race Configuration file

RCG = Netscape newsgroup file (netsc.rcg)

RCL = EasyCDCreator.Document.8 open with: "%Applications%\WinonCD8\Creator Classic\Creator8.exe" "%1"

RCP = Recomposer's MIDI Sequencer Music File

RCT = Mime: application/prs.nprend

RCT = Ms Developer Studio resource template

RCV = Resource Compiler; Resource script

RD1 = DATAIR Retirement Document System Data File

RD2 = DATAIR Retirement Document System Custom Text File

RD3 = Ray Dream Designer 3 graphics

RD3A = (MAC FILE_TYPE) Ray Dream Designer

RD3F = (MAC FILE_TYPE) CorelDraw 3D File

RD3F = (MAC FILE_TYPE) Ray Dream 3 Mode

RD4 = Ray Dream Designer Graphics

RD4A = (MAC FILE_TYPE) Ray Dream Studio

RD4F = (MAC FILE_TYPE) Ray Dream 4 Model

RD5 = Ray Dream Designer Graphics

RDB = Netscape Communicator Aim file

RDC = "IBM Voice Type" languages scripts Data file

RDEF = Geoworks UI resource file (old)

RDEV = (MAC FILE_TYPE) Chooser Device

RDF = Compiled UIC source code (Geoworks UI Compiler)

RDF = Resource Description Framework file

RDI = Device independent bitmap file (RIFF RDIB format)

RDL = Paradox

RDLC = VisualStudio.rdlc.9.0 open with: "%ProgramFiles%\Microsoft Visual Studio 9.0\Common7\IDE\devenv.exe" /dde Content Type application/xml

RDOFF = Programming

RDP = RDP.File special configuration file for application(binary format)

RDS = Ray dream 3d amination

RDV = Ntgraph Borland C 32 file

RDX = Database; Borland Reflex

RE_ = EPSON CALIBRATION file

REA = Doc Free Geocom file

REA = readme text file

README = text file

REC = ARCSERVE archivation protocol

REC = EpiInfo datafile

REC = Sprint record

REC = Windows Macrorecorder macro

RED = Clarion Modula-2 path info

RED = Rational Rose module diagram

REF = Cross-reference

REF = Reference; (generic name)

REG = Registration information/key for W95/98...

Regi = (MAC FILE_TYPE) Kagi Register Program

REGS = (MAC FILE_TYPE) Netscape Registry

RELS = xmlfile open with: "%ProgramFiles%\Common Files\Microsoft Shared\OFFICE12\MSOXMLED.EXE" /verb open "%1" ContentType application/vnd.ms-package.relationships+xml

RELS = xmlfile open with: "%ProgramFiles%\Gemeinsame Dateien\Microsoft Shared\OFFICE12\MSOXMLED.EXE" /verb open "%1" ContentType application/vnd.ms-package.relationships+xml

RELS = xmlfile open with: "%ProgramFiles%\Internet Explorer\iexplore.exe" -nohome ContentType application/vnd.ms-package.relationships+xml

REM = REMarks

REN = Gen. renamed file

RENDERMAN = Pixar RenderMan 3.1 specification

reno = (MAC FILE_TYPE) Apple Guide

REP = AAICWpro autoresponder file

REP = Mime: application/vnd.businessobjects

REP = Qwk reader REPly file

REP = REPort file made by several programs

REP! = (MAC FILE_TYPE) Replica

REPORT = Report chemical modeller output file

REQ = REQuest

RES = Compiled resource Ms C, C++

RES = Compiled Resources Borland C++

RES = XBoard resign conferences file

RESMONCFG = Diagnostic.Resmon.Config open with: %SystemRoot%\system32\perfmon /res /load "%1"

RET = Basic Realizer Careal Caret Samples file

REV = FrameMaker document; see MIF

REV = Geoworks revision file

REV = Revolution stack

REX = Oracle report definition

REX = PharLab executable file (old format)

REX = Rexx language source code

REXX = Mime: text/x-script.rexx

REXX = Rexx language source code

REZ = Resource file

RF = Bitmap image (Raster File)

RF = FrameMaker document

RF = Mime: image/vnd.rn-realflash

RF = RealFlash Clip

RFB = RoboForm

RFD = RecogniFORM Form Definition

RFG = RFG Integrator System Database

RFH = RFG Integrator Householding Database

RFM = Rich music format

RFT = Document; IBM DisplayWrite RFT-DCA

RFX = Modula M2sds file

RG = Bitmap image (1bit B&W 4bit CMYK) (Raster Graphics format)

RGB = Bitmap picture

RGB = Mime: image/x-rgb

RGB = SGI RGB files (Silicon Graphics)

RGB = Silicon Graphics Raw Red, Green and Blue bytes bitmap image

RGB = VideoCraft GIF

RGBA = Raw Red, Green, Blue and intensity bytes

rgDB = (MAC FILE_TYPE) Adobe Registration DB

RGE = Inno Setup Registry Entries file

RGH = ZZ RouGH image/tbv

RGI = RealArcade Game Installer (not secured)

RGN = DDTitle.Project open with: %ProgramFiles%\DDTITLE\ddtitle.exe "%1"

RGN = DDTitle.Project open with: DDTITLE

RGP = RealArcade Game Package

RGS = Script for Windows Registry

RGX = Symbol tables etc. info (ReaGeniX code generator)

RH = Resource Header (Borland C++/Visual C++)

RI = Lotus 1-2-3 data

RIA = Alpharel Group IV bitmap

RIB = 3d graphics (3D Reality)

RIB = 3d graphics (Renderman Interface Bytestream)

RIC = Ricoh fax

RICHMEDIA = Norton Guides file

RIF = Recource Interchange File Format bitmap image

RIFF = (MAC FILE_TYPE) Painter Image

RIFF = Recource Interchange File Format bitmap image

RIP = Quincy program crash report

RIP = Remote Access graphics

RIP = Telegrafx Remote Imaging Protocol (Maximus 3.0)

RIR = Spaceward Satori family native (Windows)

RIS = Hdf Zlib file

RIS-RM8 = risfile-rm8 open with: %ProgramFiles%\GEMEIN~1\Risxtd\Risweb32.exe "%1" Content Type application/x-Research-Info-Systems-RM8

RISCOS = (makefile for )riscos file

RIX = Bitmap image (RIX Softworks Paint Tool ColoRIX file)

RJS = Mime: application/vnd.rn-realsystem-rjs

RJS = RealSystem Skin

RKV = RKIVE compressed file archive

RL$ = Basic Realizer Disk1 file

RL1 = Descent1 Registered Level File

RL2 = Descent2 Registered Level

RL4 = Bitmap image

RL8 = Bitmap image

RLA = Alias/Wavefront bitmap image

RLB = Alias/Wavefront bitmap image

RLB = Harvard Graphics Win data

RLC = Bitmap image (Run Length RLC file)

RLC = Mime: image/vnd.fujixerox.edmics-rlc

RLC2 = Image Systems RLC2 Graphic image format

RLD = Norton Commander 5.0 temporary file

RLE = Intergraph Format image format

RLE = Run Length Encoded bitmap image

RLE = same as bmp

RLE = Utah raster bitmap image

RLF = Mime: application/x-richlink

RLF = RichLink compiled format

RLG = Regcleaner Languages file

RLL = Basic Realizer Careal file

RLO = Basic Realizer Careal Lib file

RLV = Basic Realizer Careal Clipart file

RLZ = Realizer source code file (CA-Realizer)

RM = Mime: application/vnd.rn-realmedia

RM = Mime: application/x-pn-realaudio

RM = Mime: audio/x-pn-realaudio

RM = Mime: audio/x-pn-realaudio-plugin

RM = RealMedia

RMAP = Real Pool Image

RMD = Microsoft RegMaid document

RME = Sb_awe keys file

RMF = Beatnik Rich Music Format

RMF = RealMedia File

RMI = MIDI-sequention music (RIFF RMID format)

RMI = Mime: audio/mid

RMJ = rmjfile special configuration file for application(binary format)

RMK = Makefile (CA Clipper RMake)

RMM = Mime: audio/x-pn-realaudio

RMM = RealMedia audio (RealPlayer)

RMP = Mime: application/vnd.rn-rn_music_package

RMP = Mime: audio/x-pn-realaudio

RMP = Mime: audio/x-pn-realaudio-plugin

RMP = RealAudio audio file

RMX = Mime: application/vnd.rn-realsystem-rmx

RMX = RealJukeBox MP3 File

RN = Xpl program (Nota Bene)

RND = AutoCAD Autoshade rendering slide

RND = Mime: application/prs.nprend

RND = PGP Random Seed

RNG = Mime: application/ringing-tones

RNG = Mime: application/vnd.nokia.ringing-tone

RNG = Nokia Communicator ringing tone

RNK = Dial-up shortcut

RNL = GTX runlength encoded bitmap graphics

RNO = Runoff file (VAX)

RNX = Mime: application/vnd.rn-realplayer

RNX = RealPlayer audio

ROB = Dllbackup microsoft artgalary file

ROCKWELL = rockwell (modem) file

ROFF = Mime: application/x-troff

ROFF = Unformatted manual page (Roff/nroff/troff/groff)

rohd = (MAC FILE_TYPE) Read-Only Disk Image

ROL = Adlib syntesized music (Roland)

ROM = Read Only Memory image (emulators/AONs)

RonA = (MAC FILE_TYPE) Graphing Calculato

ROT = Rotater 3D image

ROV = Rescure Rover game data

ROXIO = RoxioCentral.File open with: "%ProgramFiles%\Gemeinsame Dateien\Roxio Shared\Roxio Central\Main\Roxio_Central.exe" "%1"

ROY = TrueType

RP = Mime: image/vnd.rn-realpix

RP = Rainbow Painter image format

RP = RealPix image

RP1 = Database Text; R&R report file

RP3 = Game: need for speed car race file

RPB = CP Backup report

RPBM = Portable Bitmap image format

RPC = ACT! 2.0 Report

RPD = Database; Ashton Tate RapidFile

RPF = AutoCAD pattern

RPG = The RPG programming language

RPGM = Portable Image

RPI = "solid free form fabrication" flexible file format

RPJ = RealSlideshow Project

RPL = Document (Replica)

RPL = RePLy message

RPM = Linux Package Manager( installing, uninstalling, verifying, querying, and updating software packages)

RPM = Mime: application/x-pn-realaudio

RPM = Mime: audio/x-pn-realaudio-plugin

RPM = Mime: audio/x-pn-RealAudio-plugin

RPM = RealAudio plugin

RPM = RunPaint (Multicolor) image format

RPN = ACT! 2.0 Report

RPNM = Portable Image image format

RPPM = Portable Image

RPR = "IBM Voice Type" languages Vocabels file

RPT = Microsoft Visual Basic Crystal Reports file

RPV = Listlabl file

RQY = MS Excel OLE DB Query File

RRF = Musicmatch Jukebox file

RRS = Road Rash Save File

RS = Data file (Amiga Resource/Reassembler)

RS = Sun Raster Images image format

RS6000 = Rs 6000 (make-)file

RS_ = Resource fork of a Macintosh file (Mac-ette)

RSA = PKCS7 signature, MD5 + RSA

RSB = Red Storm Bitmap. RSB plugins for Photo or Paint Shop http://www.deadlyforcegaming.com/

RSC = Compiled ReSourCe(s)

RSD = Roland sound file

RSD = Scanner Recognita file

RSDF = rsdf open with: "%Root%\cryptload1.6\CryptLoad.exe" "%1"

RSDF = rsdf open with: "%Root%\Tools\CryptLoad_1.0.4\CryptLoad.exe" "%1"

RSED = (MAC FILE_TYPE) ResEdit

RSET = (MAC FILE_TYPE) Extensions Manager Set

RSF = Mediafour MacDrive Macintosh Resource Fork

RSG = Compiled resource header (EPOC)

RSK = Risk project (RiskMan)

RSL = Paradox (used with FSL)

RSL = PC Tools for Win ReSource Library

RSM = Mime: model/vnd.gdl

RSM = Mime: model/vnd.gs.gdl

RSM = Resume file (WinWay Resume Writer)

RSML = Mime: application/vnd.rn-rsml

RSML = RealSystem ML File

RSN = Propellerhead Reason Audio File

RSP = Linker response file (generic)

RSRC = icnsfile open with: "%ProgramFiles%\Axialis\IconWorkshop\IconWorkshop.exe" %1

RSRC = (MAC FILE_TYPE) Resource File

rsrc = (MAC FILE_TYPE) Resource Filek ImageBrsrc

RSRC = ReSouRCe rsrc files Type "RSRC" Creator "RSED" (MAC)

RSS = Resource source file (EPOC)

RsSc = (MAC FILE_TYPE) Claris Resolve Script

RST = "IBM Voice Type" languages scripts Data file

RSX = data base file (from ????)

RT = Mime: text/richtext

RT = Mime: text/vnd.rn-realtext

RT = Rich Text

RT = Behemot 3d Scene Files

RT$ = Ntgraph Visual c wizzard file

RT_ = Winhelp file (compressed)

RTA = "IBM Voice Type" languages Vocabels file

RTB = Behemot binary 3d Scene Files

RTC = Rescue Me file

RTCP = Realtime Transport Control Protocol

RTD = Ragtime examples render file

RTE = Mime: x-lml/x-gps

RTF = Mime: application/msword

RTF = Mime: application/rtf

RTF = Mime: application/x-rtf

RTF = Mime: text/richtext

RTF = Mime: text/rtf

RTF = Rich Text Format document

RTF_ = (MAC FILE TYPE) RTF File

RTF_ = (MAC FILE TYPE) RTF produced by Microsoft Word (PC ext: RTF)

RTF_ = (MAC FILE_TYPE) Rich Text Format Filetrtf

RTFD = RTF-Packet (NeXT)

RTG = Mime: application/metastream

RTH = ANSYS Results

RTK = RoboHelp Configuration

RTL = Bitmap image (HP Raster Transfer Language) (HP colour printers)

RTL = Norton Utilities runtime library

RTL = Text file

RTM = Real Tracker music module (MOD) file

RTP = MS patch file (usually MS VC++)

RTP = Software update file (.RTPatch)

RTR = "IBM Voice Type" languages Vocabels file

RTS = CA-Realizer runtime library

RTS = Mime: application/x-rtsl

RTS = RealAudio's RTSL document

RTSL = Real document

RTT = Ragtime file

RTX = Mime: application/rtf

RTX = Mime: text/richtext

RTX = Text document

RU = Javasoft Jre 1.3 lib file

RUL = Expert System Rule

RUL = Rules (Echo-conference)

RULE = (MAC FILE_TYPE) Microsoft Rules File

RUN = PC Tools for Win batch file

RUS = Russian text

RV = Mime: video/vnd.rn-realvideo

RV = RealVideo video

RVP = Microsoft Scan Configuration file

RVW = ReVieW

RWS = Borland C++ Resource Workshop Symbol file

RWX = Criterion RenderWare script/extruded text

RWX = MEME Shape File

RWX = Netscape Live 3D; see FLR

RWZ = MS OutlookXP Internet Settings

RX = Dos7 file

RXD = Reflex datafile

RXH = Reflex Database Help File

RXML = Roxen Macro Language

RXN = MDL Reaction format

RXN = Mime: chemical/x-mdl-rxn

RXN = Mime: chemical/x-mdl-rxnfile

RXR = Reflex Report

RXS = Reflex Database Screen Driver

RXX = RAR compressed files from a multi-volume archive (xx = a number from 01 to 99)

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Universal dump-utility for non-destructive dump/list/search string etc dump.zip

Select Extension by starting letter:

A- B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U -

V- W - X - Y - Z - OTHER - Allowed chars in Filenames - what is an extension?

If you find an extension missing, write! No guarantee given for completeness or correctness. If you feel an extension is outdated, write!
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Compilation Copyright (c) 2002 R.Bitsch, Compilation Copyright (c) 2009,2010 R.Cooper-Bitsch