| Extension | Summary |
|---|
| .G | BRL-CAD Geometry File |
| .G1A | Casio Graphing Calculator Add-in File |
| .G1M | Casio Graphing Calculator Memory File |
| .G2M | GoToMeeting Recording File |
| .G3A | Casio Prizm Add-in File |
| .G3D | GOM 3D File |
| .G3F | Zetafax Fax Image |
| .G3M | Casio fx-CG Prizm Memory File |
| .G3N | Zetafax Fax Image |
| .G3X | RealFlight Content File |
| .G41 | Commodore 1541 Disk Image |
| .G64 | Genetec Video File |
| .G64X | Genetec Video File |
| .G721 | G.721 Audio File |
| .G722 | G.722 ADPCM Audio File |
| .G723 | G.723 Audio File |
| .G726 | G.726 Audio File |
| .GA | Genetic Art Image Parameters |
| .GA3 | Graphical Analysis 3 Document |
| .GADGEPRJ | Gadge It Project |
| .GADGET | Windows Gadget |
| .GAL | GenePix Array List File |
| .GALAXY | Blizzard Galaxy File |
| .GALLERY | SMART Notebook Gallery File |
| .GALLERYCOLLECTION | SMART Notebook Gallery Collection File |
| .GALLERYITEM | SMART Notebook Gallery Item File |
| .GAM | Saved Game File |
| .GAME | GameSalad Exported Game File |
| .GAMEDATA | Sandlot Game Data File |
| .GAMEPROJ | GameSalad Project File |
| .GAN | GanttProject Project File |
| .GAR | GridGain Archive |
| .GAU | Flight Simulator Gauge File |
| .GB | Game Boy ROM File |
| .GB1 | Game Maker Backup File |
| .GB2 | Game Maker Backup File |
| .GBA | Game Boy Advance ROM |
| .GBAP | GLBasic Project File |
| .GBAS | GLBasic Source File |
| .GBASKIN | Game Boy Advance Controller Skin File |
| .GBC | Game Boy Color ROM |
| .GBCSKIN | Game Boy Color Controller Skin File |
| .GBI | gBurner Project File |
| .GBK | GenBank Data File |
| .GBL | Gerber Bottom Layer Data File |
| .GBLORB | Glulx Blorb Game File |
| .GBM | Gameboy Map File |
| .GBO | Gerber Bottom Overlay Data File |
| .GBP | Genie Timeline Backup Index File |
| .GBPROJ | GarageBand Project |
| .GBR | Gameboy Tileset File |
| .GBS | Generic Build Support Metadata File |
| .GBX | Gerber PCB File |
| .GC | Galactic Conquest Saved Game |
| .GCA | GCA File Archive |
| .GCD | Prassi CD Image |
| .GCDP | Greeting Card Studio Design Project |
| .GCF | Game Cache File |
| .GCG | GCG DNA Sequence File |
| .GCH | Precompiled Header File |
| .GCI | GameCube Saved Game |
| .GCM | GameCube ROM |
| .GCODE | G-Code 3D Printer File |
| .GCPROJ | Genome Compiler Project |
| .GCS | GameCube SharkSave File |
| .GCSX | Microsoft Office SmartArt Color File |
| .GCT | Ocarina Cheat Code Manager File |
| .GCW | Microsoft Mathematics Worksheet |
| .GCX | Grapher Graph File |
| .GCZ | Compressed GameCube/Wii ROM |
| .GD | Godot Engine Script |
| .GD3 | GreatFamily Genealogy Data File |
| .GDB | GPS Database File |
| .GDBTABLE | Geodatabase Table File |
| .GDC | Godot Engine Compiled Script |
| .GDCB | GandCrab Ransomware Encrypted File |
| .GDE | The Guide Document |
| .GDF | GUESS Graph Data Format File |
| .GDFMAKERPROJECT | GDF Editor Project File |
| .GDG | GDevelop Project File |
| .GDG.AUTOSAVE | GDevelop Project Autosave File |
| .GDI | Dreamcast Gigabyte Disc Image |
| .GDIAGRAMSTYLE | OmniGraffle Diagram Style File |
| .GDOC | Google Docs Shortcut |
| .GDOCX | Google Drive Document |
| .GDR | Symbian OS Font File |
| .GDRAW | Google Drawings Shortcut |
| .GDRIVE | Gizmo Virtual Drive File |
| .GDS | Graphic Data System File |
| .GDT | gretl Datafile |
| .GDTB | gretl Binary Datafile |
| .GDV | Gremlin Digital Video |
| .GDW | Jaws Unleashed Data File |
| .GDZ | GEDZip Genealogy Data File |
| .GED | Game Editor Project File |
| .GEDATA | Qlucore Data File |
| .GEDCOM | GEDCOM Genealogy File |
| .GEM | RubyGems Package |
| .GEMSPEC | Gem Specification File |
| .GEN | Sega Genesis ROM |
| .GENBANK | GenBank Data File |
| .GENERICTEST | Visual Studio Generic Test File |
| .GENOME | Cell Lab Design File |
| .GEO | TruTops Geometry File |
| .GEOJSON | GeoJSON File |
| .GEXF | Graph Exchange XML Format File |
| .GF | METAFONT Bitmap File |
| .GFAR | Greenfoot Archive |
| .GFB | GIFBlast Compressed Image File |
| .GFE | Glarysoft Encrypted File |
| .GFI | GIFI File |
| .GFIE | Greenfish Icon Editor Pro Graphic |
| .GFORM | Google Forms Shortcut |
| .GFP | GreenForce-Player Protected Media File |
| .GFS | Glarysoft Split File |
| .GFW | GIF World File |
| .GFX | GFx Scaleform File |
| .GG | Google Desktop Gadget File |
| .GGB | GeoGebra Worksheet |
| .GGP | OtterUI Project File |
| .GGPACK | Thimbleweed Park Resource Archive |
| .GGR | GIMP Gradient File |
| .GHB | Lego Ghost Path File |
| .GHO | Norton Ghost Backup File |
| .GHS | Norton Ghost Image Segment |
| .GI | Global Image |
| .GID | Windows Help Global Index File |
| .GIF | Graphical Interchange Format File |
| .GIFV | GIF Video File |
| .GIG | Tascam GigaSampler File |
| .GIH | GIMP Image Hose File |
| .GIM | PlayStation Portable Image File |
| .GIN | GEMS Engine Control Unit File |
| .GINSPECT_PRJ | GOM Inspect Project File |
| .GIO | Nyquist MIDI File |
| .GIS | CFS Console Game Installer Settings File |
| .GITATTRIBUTES | Git Attributes File |
| .GITIGNORE | Git Ignore File |
| .GITKEEP | Git Keep File |
| .GIVEMENITRO | Nitro Ransomware |
| .GJAM | Google Jamboard Shortcut |
| .GJD | The 7th Guest Media File |
| .GKH | Ensoniq EPS Family Disk Image |
| .GKS | Graphics Kernel System File |
| .GL | GRASP Animation |
| .GLA | Ghoul 2 Animation File |
| .GLADE | Glade Project File |
| .GLB | STK Globe File |
| .GLD | MPLAB C Compiler Linker Script File |
| .GLF | Space Engine Shader File |
| .GLIF | Glyph Interchange Format File |
| .GLIFFY | Gliffy Diagram File |
| .GLINK | Google Drive External File Shortcut |
| .GLKSAVE | Zoom Game Save Package |
| .GLM | Ghoul 2 Model File |
| .GLO | RoboHelp Glossary File |
| .GLOBAL | Global Makefile |
| .GLOX | Microsoft Office SmartArt Graphics Layout File |
| .GLS | GLScript Game Script |
| .GLTF | GL Transmission Format File |
| .GLY | Microsoft Word Glossary File |
| .GM | GameMonkey Script |
| .GM6 | GameMaker 6 Project File |
| .GM81 | Game Maker 8.1 Project File |
| .GMA | Garry's Mod Addon File |
| .GMAP | Garmin Map File |
| .GMBCK | Game Maker Background Image File |
| .GMBL | Logger Lite Document |
| .GMC | Game Music Creator Sound File |
| .GMD | Game Maker Program Code |
| .GME | DexDrive Game Card File |
| .GMF | Geology Multi-File |
| .GMK | GameMaker Project File |
| .GML | GameMaker Language File |
| .GMM | Nintendo Game Message |
| .GMMOD | Game Maker 3D Model File |
| .GMMP | WCS Gamut Map Model Profile |
| .GMO | GNU Machine Object File |
| .GMP | Global Mapper Package File |
| .GMRES | GameMaker Resource File |
| .GMS | Garry's Mod Save File |
| .GMSPR | Game Maker Sprite File |
| .GMT | rFactor Model File |
| .GMV | Gens Game Recording |
| .GMW | Global Mapper Workspace File |
| .GMX | GameMaker File |
| .GMZ | Compressed GameMaker File |
| .GNE | Flickr Webpage |
| .GNM | Gnumeric Spreadsheet |
| .GNO | GenoPro Genealogy Tree File |
| .GNP | GenePool Save File |
| .GNUMAKEFILE | GNU Makefile |
| .GNUMERIC | Gnumeric Spreadsheet |
| .GNUTAR | GNU Tar Archive |
| .GO | Go Source Code File |
| .GOD | God Configuration File |
| .GODOT | Godot Engine Project |
| .GOFIN | DRUKI Gofin Form File |
| .GOOMOD | World of Goo Add-on |
| .GORM | Gorm Interface Resource File |
| .GP3 | Guitar Pro 3 File |
| .GP4 | Guitar Pro 4 Tablature |
| .GP5 | Guitar Pro 5 Tablature File |
| .GPBANK | Guitar Pro Sound Bank File |
| .GPD | Gamer Profile Data File |
| .GPE | GP2X Video Game |
| .GPF | Geosoft Project File |
| .GPG | GNU Privacy Guard Public Keyring |
| .GPI | Garmin Point of Interest File |
| .GPJ | jGRASP Project File |
| .GPK | WaveLab Audio Peak File |
| .GPN | GlidePlan Map Document |
| .GPP | Guitar Practiced Perfectly 2 Data File |
| .GPR | Babylon Glossary Builder Project File |
| .GPRX | Geoxa Project File |
| .GPS | GOM Player Skin File |
| .GPSCAN | GrandPerspective Scan File |
| .GPU | GP2X Utility Program |
| .GPX | GPS Exchange File |
| .GQSX | Microsoft Office SmartArt Styles File |
| .GR2 | Granny 3D File |
| .GRA | Microsoft Graph File |
| .GRADE | GradeStat Document |
| .GRADIENTLIBRARY | Painter Gradient Library |
| .GRADIENTS | Painter Gradation Library |
| .GRADLE | Gradle Script |
| .GRAFFLE | OmniGraffle Drawing |
| .GRAPHML | GraphML File |
| .GRAPHMLZ | Zip Compressed GraphML File |
| .GRB | GRIB Meteorological Data File |
| .GRD | Photoshop Gradient File |
| .GRDB | Gramps Database File |
| .GREENFOOT | Greenfoot Project Archive |
| .GRF | Transport Tycoon Graphics Resource File |
| .GRIB | Gridded Binary File |
| .GRIB2 | GRIB2 Meteorological Data File |
| .GRIND | Juice Grinder Recipe File |
| .GRINDX | Juice Grinder Recipe File |
| .GRK | Gradekeeper Class Gradebook File |
| .GRL | Windows Update Status File |
| .GRN | Granny 3D File |
| .GRO | Graphic Object Bitmap |
| .GROOVE | ACID Groove File |
| .GROOVY | Groovy Source Code File |
| .GROUP | Windows Contacts Group File |
| .GROUPPROJ | Delphi Project Group File |
| .GROWLREGDICT | Growl Temp File |
| .GROWLTICKET | Growl Notification File |
| .GRP | Windows Program Manager Group |
| .GRR | Gradekeeper Class Roster File |
| .GRS | Gravity Sketch Sketch File |
| .GRT | Grapher Template |
| .GRV | Office Groove File |
| .GS | Google Apps Script |
| .GS-BCK | Genius Scan Backup File |
| .GS0 | Sega Genesis Emulator Quick Slot 0 Save File |
| .GS3 | GameStarter File |
| .GSB | Golden Software Boundary File |
| .GSBA | Game Save Backup Archive |
| .GSC | Call of Duty Game Script |
| .GSCRIPT | Google Apps Script Shortcut |
| .GSD | Graphtec Vector Graphics File |
| .GSF | Game Boy Advance Sound File |
| .GSFLIB | Game Boy Advance Song Library |
| .GSHEET | Google Sheets Shortcut |
| .GSI | Golden Software Interchange File |
| .GSITE | Google Sites Shortcut |
| .GSLIDES | Google Slides Shortcut |
| .GSM | MapViewer Project File |
| .GSP | Geometer's Sketchpad File |
| .GSPROJ | GameSalad Windows Project File |
| .GSR | Golden Software Reference File |
| .GSR2 | Golden Software Reference File |
| .GST | MapInfo Geoset File |
| .GSTENCIL | OmniGraffle Stencil |
| .GSX | Sega Genesis Emulator Saved State File |
| .GSZIP | GameSalad Marketplace Asset File |
| .GTA | Microsoft Groove Tool Archive |
| .GTABLE | Google Fusion Table Shortcut |
| .GTAR | GNU Tar Archive |
| .GTEMPLATE | OmniGraffle Template |
| .GTHR | Gather Log File |
| .GTKRC | GTK+ Theme File |
| .GTL | Gerber Top Layer Data File |
| .GTM | GPS TrackMaker Data File |
| .GTO | Gerber Top Overlay Data File |
| .GTP | GNOME Theme Package File |
| .GTS | CaptiveWorks PVR Video File |
| .GTWORLD | Growtopia World File |
| .GUI | Dr.Explain Project File |
| .GUIDES | xScope Guides File |
| .GUIT | Rust Guitar Song file |
| .GV | Graphviz DOT File |
| .GVDESIGN | Gravit Designer File |
| .GVI | Google Video File |
| .GVIMRC | GVim Runtime Configuration File |
| .GVP | Google Video Pointer |
| .GVSP | Geocortex Viewer for Silverlight Project |
| .GVSWATCH | Gravit Designer Swatch File |
| .GVY | Groovy Source Code File |
| .GW | GeneWeb Source File |
| .GWB | Interwrite Presentation File |
| .GWD | Galaxy Watchface Design File |
| .GWI | GroupWise Database Shortcut File |
| .GWK | GraphiCode PCB Job File |
| .GWP | Greetings Workshop Project File |
| .GWS | GeoMedia GeoWorkspace File |
| .GXC | General CADD Pro Component |
| .GXD | General CADD Pro Drawing |
| .GXF | General CADD Pro Font File |
| .GXH | General CADD Pro Hatch Pattern File |
| .GXK | Galaxkey Secured File |
| .GXL | Graph Exchange Language File |
| .GXM | General CADD Pro Macro File |
| .GXT | Grand Theft Auto Text File |
| .GYM | Sega Genesis Sound File |
| .GZ | Gnu Zipped Archive |
| .GZ2 | Misnamed BZ2 File |
| .GZA | IZArc BGA Archive File |
| .GZI | Unix Gzip File |
| .GZIP | Gnu Zipped File |
| .GZQUAR | Bitdefender Antivirus Quarantine File |
