| .RIA | Unknown Developer | Raster Image Files | Alpharel Group IV Raster Graphics File | Unknown Software | Unknown Developer |
| .RIC | The LEGO Group | Raster Image Files | NXT Image File | LEGO MINDSTORMS NXT | The LEGO Group |
| .RID | Bronzware Inc | Raster Image Files | GerbMagic Graphics | GerbMagic | Bronzware Inc |
| .RIF | Corel | Raster Image Files | Painter Raster Image | Corel Painter | Corel |
| .RIFF | Corel | Raster Image Files | Painter Raster Image | Corel Painter | Corel |
| .RIX | RIX SoftWorks, Inc. | Raster Image Files | ColoRIX Image File | ColoRIX | RIX SoftWorks, Inc. |
| .RL4 | Various Developers | Raster Image Files | Bitmap Image File | Adobe Illustrator CC | Adobe Systems Incorporated |
| .RLA | Wavefront Technologies | Raster Image Files | Alias/Wavefront Image File | XnView MP | XnSoft |
| .RLE | Various Developers | Raster Image Files | Run Length Encoded Bitmap | Canvas X | ACD Systems |
| .RLI | RealWorld Graphics | Raster Image Files | RealWorld Graphics Layered Image | RealWorld Icon Editor | RealWorld Graphics |
| .RNL | GTX | Raster Image Files | GTX Runlength Encoded Bitmap Graphics | GTXRaster CAD | GTX |
| .RPF | Rockstar Games | Raster Image Files | Grand Theft Auto Data File | Grand Theft Auto IV | Rockstar Games |
| .RRI | Astronomical Institute of the Czech Academyof Sciences | Raster Image Files | SPEFO Stellar Spectra Analysis Data | SPEFO | Astronomical Institute of the Czech Academyof Sciences |
| .RSB | ReliaSoft | Raster Image Files | ReliaSoft BlockSim File | ReliaSoft BlockSim | HBM PRENSCIA INC. |
| .RSR | Smith Micro Software | Raster Image Files | Poser Model Preview File | Smith Micro Poser | Smith Micro Software |
| .RSS | Various Developers | Raster Image Files | Rich Site Summary | Mozilla Firefox | Mozilla |
| .RTL | Hewlett-Packard | Raster Image Files | Raster Transfer Language File | SwiftView | SwiftView, Inc. |
| .RVG | Autodesk, Inc. | Raster Image Files | Revit External Group File | Revit | Autodesk, Inc. |
| .SAI | SYSTEMAX Software Development | Raster Image Files | PaintTool SAI Image | PaintTool SAI | SYSTEMAX Software Development |
| .SAI2 | SYSTEMAX Software Development | Raster Image Files | Paint Tool SAI Version 2 Drawing | PaintTool SAI | SYSTEMAX Software Development |
| .SAR | Commodore International | Raster Image Files | Saracen Paint Image | XnView MP | XnSoft |
| .SBP | Autodesk, Inc. | Raster Image Files | Sketchbook Express iCloud Image | SketchBook | Autodesk, Inc. |
| .SCANNER | Unknown Developer | Raster Image Files | Scanner Output File | Unknown Software | Unknown Developer |
| .SCG | Midori Media | Raster Image Files | MyPM SCG Definition File | Midori Media myPM SCG Classic | Midori Media |
| .SCN | Microsoft Corporation | Raster Image Files | Age Of Mythology Scenario File | Microsoft Age of Empires | Ensemble Studios |
| .SCP | RIX SoftWorks, Inc. | Raster Image Files | ColoRIX Bitmap Graphic File | XnView MP | XnSoft |
| .SCT | Scitex | Raster Image Files | Scitex Continuous Tone File | Adobe Photoshop | Adobe Systems Incorporated |
| .SCU | RIX SoftWorks, Inc. | Raster Image Files | ColoRIX Bitmap Graphic File | XnView MP | XnSoft |
| .SCX | RIX SoftWorks, Inc. | Raster Image Files | ColoRIX Bitmap Graphic File | XnView MP | XnSoft |
| .SDG | Golden Software LLC | Raster Image Files | Strater Project File | Strater | Golden Software LLC |
| .SDR | Dell Boomi | Raster Image Files | Dell Support File | Unknown Software | Unknown Developer |
| .SEP | PictView software | Raster Image Files | Separated Image File | PictView | PictView software |
| .SFC | Unknown Developer | Raster Image Files | Super Nintendo ROM | Snes9x | Snes9x Team |
| .SFF | Elecbyte | Raster Image Files | M.U.G.E.N. Sprite File | Elecbyte M.U.G.E.N | Elecbyte |
| .SFW | Seattle Lab | Raster Image Files | Seattle FilmWorks Image | Lemkesoft GraphicConverter | Lemkesoft |
| .SGD | Syngene | Raster Image Files | GeneSnap Image File | GeneSnap | Syngene |
| .SGI | Silicon Graphics, Inc. | Raster Image Files | Silicon Graphics Image File | Canvas X | ACD Systems |
| .SHG | Microsoft Corporation | Raster Image Files | Segmented Hyper-Graphic | Microsoft WinHelp | Microsoft Corporation |
| .SID | Valve | Raster Image Files | Steam Game Data Backup File | Steam | Valve |
| .SIG | Unknown Developer | Raster Image Files | Signature File | Microsoft Outlook Express | Microsoft Corporation |
| .SIM | Valve | Raster Image Files | Steam Game Backup Information File | Steam | Valve |
| .SIX | Digital Equipment Corporation | Raster Image Files | DEC LN03+ Sixel Bitmap Image File | Unknown Software | Unknown Developer |
| .SKM | Trimble Inc. | Raster Image Files | SketchUp Materials File | SketchUp | Trimble Inc. |
| .SLD | ESRI (Environmental Systems Research Institute) | Raster Image Files | Styled Layer Descriptor | ESRI ArcGIS for Desktop | ESRI (Environmental Systems Research Institute) |
| .SMP | MakeMusic, Inc. | Raster Image Files | SmartMusic Performance File | SmartMusic | MakeMusic, Inc. |
| .SNAP | Erik Kunze | Raster Image Files | ZX Spectrum Emulator Mirage Microdrive Snapshot | XZX-Pro | Erik Kunze |
| .SOB | Apache Software Foundation | Raster Image Files | OpenOffice.org Impress Bimap Styles File | Apache OpenOffice | Apache Software Foundation |
| .SPA | Yu Higuchi | Raster Image Files | MikuMikuDance Sphere Mapping File | MikuMikuDance | Yu Higuchi |
| .SPC | Various Developers | Raster Image Files | Software Publisher Certificate File | OpenSSL | Open Source |
| .SPE | IBM | Raster Image Files | SPSS Extension | IBM SPSS | IBM |
| .SPH | National Institute of Standards and Technology (NIST) | Raster Image Files | NIST SPHERE Audio File | SoX | Open Source |
| .SPIFF | Joint Photographic Experts Group | Raster Image Files | Still Picture Interchange File Format | Unknown Software | Unknown Developer |
| .SPJ | IBM | Raster Image Files | SPSS Production Job File | IBM SPSS | IBM |
| .SPOT | SPOT Image | Raster Image Files | SPOT Satellite Image | SPOT Images | SPOT Image |
| .SPP | Serif | Raster Image Files | Serif PhotoPlus Picture File | PhotoPlus | Serif |
| .SPR | Valve | Raster Image Files | Half-Life Sprite File | Half-Life | Valve |
| .SPRITE | MIT Media Lab | Raster Image Files | Scratch Sprite File | MIT Scratch | MIT Media Lab |
| .SPS | IBM | Raster Image Files | SPSS Program File | IBM SPSS | IBM |
| .SPU | Atari Corporation | Raster Image Files | Spectrum 512 Image | Lemkesoft GraphicConverter | Lemkesoft |
| .SR | Sun Microsystems | Raster Image Files | Sun Raster Image File | GIMP | The GIMP Development Team |
| .SRS | Microsoft Corporation | Raster Image Files | Outlook Send/Receive Settings File | Microsoft Outlook | Microsoft Corporation |
| .SSI | Adobe Systems Incorporated | Raster Image Files | Adobe Dreamweaver Server Side Include File | Adobe Dreamweaver | Adobe Systems Incorporated |
| .STG | Microsoft Corporation | Raster Image Files | ActiveSync Backup File | Microsoft ActiveSync | Microsoft Corporation |
| .SUL | Unknown Developer | Raster Image Files | GFA Raytrace Image | GFA Raytrace | Unknown Developer |
| .SUN | Sun Microsystems | Raster Image Files | Sun Raster Graphic File | GIMP | The GIMP Development Team |
| .SUNIFF | Sun Microsystems | Raster Image Files | Sun TAAC Image | XnView MP | XnSoft |
| .SUP | Unknown Developer | Raster Image Files | Subtitle Bitmap File | IfoEdit | Open Source |
| .SVA | Viz Media | Raster Image Files | Manga Browser Comic File | Sharp Manga Browser for SHONEN JUMP | Viz Media |
| .SVM | Star Division | Raster Image Files | StarView Metafile | Apache OpenOffice | Apache Software Foundation |
| .SVS | Nintendo | Raster Image Files | Game Boy Advance Saved State File | Game Boy Advance | Nintendo |
| .T1 | XnSoft | Raster Image Files | Male MRI Image Format | XnView MP | XnSoft |
| .TAAC | Sun Microsystems | Raster Image Files | Sun TAAC Image | XnView MP | XnSoft |
| .TBN | Open Source | Raster Image Files | Kodi Thumbnail Image | Kodi | Open Source |
| .TDP | Serif | Raster Image Files | Sherif DrawPlus Thumbnail File | Serif WebPlus | Serif |
| .TEX | Open Source | Raster Image Files | LaTeX Source Document | gVim | Open Source |
| .TG4 | Bentley Systems | Raster Image Files | Tiled Group 4 Raster Image File | MicroStation | Bentley Systems |
| .TGA | Avid Technology | Raster Image Files | Targa Graphic | Adobe Illustrator CC | Adobe Systems Incorporated |
| .THM | Sony | Raster Image Files | Sony Ericsson Mobile Phone Theme File | Sony Ericsson Theme Creator | Sony Mobile Communications |
| .THUMB | Jalbum AB | Raster Image Files | JAlbum Thumbnail File | JAlbum | Jalbum AB |
| .TIF | XnSoft | Raster Image Files | Tagged Image File Format | Adobe Illustrator CC | Adobe Systems Incorporated |
| .TIFF | XnSoft | Raster Image Files | Tagged Image File Format | Adobe Illustrator CC | Adobe Systems Incorporated |
| .TILE | XnSoft | Raster Image Files | Eclipse Image | Unknown Software | Unknown Developer |
| .TIM | Sierra Entertainment | Raster Image Files | The Incredible Machine Level | The Incredible Machine | Sierra Entertainment |
| .TN1 | Atari Corporation | Raster Image Files | Tiny Low Resolution Image | Graphics Converter Pro | Newera Software Technology, Inc. |
| .TN2 | Atari Corporation | Raster Image Files | Tiny Medium Resolution Image | XnView MP | XnSoft |
| .TN3 | Atari Corporation | Raster Image Files | Tiny High Resolution Image | XnView MP | XnSoft |
| .TNY | Atari Corporation | Raster Image Files | Atari Tiny Image | Graphics Converter Pro | Newera Software Technology, Inc. |
| .TPF | IBM | Raster Image Files | SPSS Text Wizard Document | IBM SPSS | IBM |
| .TPI | Thomson Reuters Corporation | Raster Image Files | EDIUS Plugin File | Thomson EDIUS | Grass Valley |
| .TPS | TiePie engineering | Raster Image Files | Multi Channel Measurement File | Multi Channel | TiePie engineering |
| .TRIF | Tiling Task Group (TTG) | Raster Image Files | Tiled Raster Interchange Format | Unknown Software | Unknown Developer |
| .TRP | VSO Software | Raster Image Files | MPEG-2 HD Video Transport Stream | CyberLink PowerDVD | CyberLink |
| .TUB | Corel | Raster Image Files | PaintShop Pro Picture Tube | GIMP | The GIMP Development Team |
| .U | Epic Games | Raster Image Files | Unreal Tournament Class Package | Dragon UnPACKer | Open Source |
| .UFO | Ulead Systems | Raster Image Files | Ulead File Object | Ulead Photo Express | Ulead Systems |
| .ULG | Pierre-Emmanuel Gougelet | Raster Image Files | ULG Bitmap Image | XnView MP | XnSoft |
| .UPF | Bentley Systems | Raster Image Files | MicroStation User Preferences File | MicroStation | Bentley Systems |
| .UPX | Open Source | Raster Image Files | Ultimate Packer For eXecutables File | PeaZip | Open Source |
| .URT | Pierre-Emmanuel Gougelet | Raster Image Files | Utah Raster Toolkit File | XnView MP | XnSoft |
| .V | Microsoft Corporation | Raster Image Files | Subsampled Raw YUV Image | Microsoft Windows Media Player | Microsoft Corporation |
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