This alphabetical list of filename extensions contains extensions of notable file formats used by multiple notable applications or services.

A

Ext.DescriptionUsed by
AArchive filear (Unix)
Advanced Audio fileYouTube Music
Advanced Audio Coding fileiOS, Nintendo DSi, Nintendo 3DS, YouTube Music
[1]Microsoft Access DatabaseMicrosoft Access Database (Open XML)
[2]Microsoft Access Data Type TemplateMicrosoft Access
Adobe color palette format (.aco)[3]Adobe Photoshop[4]
Abrechnungsdatentransfer, an xDT applicationHealthcare providers in Germany
DocumentArchetype Designer
Amiga Disk Zipped (See Amiga Disk File)GZip
Agda (programming language) source fileAgda typechecker/compiler
ArcView ASCII grid
AutoHotkey script fileAutoHotkey
[5]Adobe Illustrator ArtworkAdobe Illustrator
[6]Audio Interchange File Formatprofessional audio processing applications and on Macintosh[7]
[6]Compressed Audio Interchange File Format
APL programming language file transfer format file
[8][9]Additive Manufacturing File FormatComputer Aided Design Software
System image fileACTOR
[10]AutomationMLAutomationML Group
[10]Compressed and packed AutomationML fileAutomationML Group
AMPL source code fileAMPL
Adaptive Multi-Rate audio
Actions Media Video
[11]Animation cursors for WinWin95 - WinNT
Annotations of old Windows Help fileWindows 3.0 - XP
Monkey's Audio (Lossless)audio media players
Android application packageAndroid
Alpine Linux Package Alpine Linux and derivatives
[12]ARC (file format)
[13]Gerber formatCadence Allegro, EAGLE
Sony Alpha RAW image formatSony
[14]ASP.NET global application file
[14]ASP.NET User Control
[15]Advanced Streaming Format (Compressed Windows audio/video)Microsoft Corporation
[14]ASP.NET handler file
Assembler language sourceTASM, MASM, NASM, FASM
Active server page extended fileMicrosoft Corporation
[16]Advanced Stream Redirector file, redirects to an ASF file (see ASF)Microsoft Corporation
[17]Coco/R LL(1) formal grammarCoco/R
[18]Atrac 3 Sound/music fileAll Sony devices and programs with the Atrac 3+ specification
audio file[19]
[20][21]Audio Video InterleaveVideo for Windows
AV1 Image File Format
AWK script/programawk, GNU Awk, mawk, nawk, MKS AWK, Awka (compiler)
DirectShow FilterMicrosoft Corporation (Video Players)
[22]lightweight geodatabaseESRI ArcPad

B

Ext.DescriptionUsed by
BBASIC language sourceBASIC
Bbc arbitrary precision calculator language fileUnix bc tool
base64 binary-to-text encoding[23]
backupvarious
[24]FMOD asset fileFMOD
Broker Archive. Compressed file containing number of other files for deployment.[25]IBM App Connect
BASIC language sourceQuickBASIC - GW-BASIC - FreeBASIC - others
Batch fileMS-DOS, RT-11, DOS-based command processors
Glyph Bitmap Distribution Format, a format used to store bitmap fonts.Adobe
Behandlungsdatentransfer, an xDT applicationHealthcare providers in Germany
Executable bytecode file in fat binary formatBEAM (Erlang virtual machine)[26]
Bibliography databaseBibTex
binary fileEvery OS
Blender project fileBlender
UIQ3 Phone backup
[27]OS/2 or Win graphics format (BitMap Picture)QPeg - CorelDraw - PC Paintbrush - many
WPS backup file[28]Microsoft Word, Microsoft Works
Bryce 7 project fileBryce 7
Bryce 7 sky presets fileBryce 7
JSON-like binary serialization[29]MongoDB
Binary space partitioning tree fileQuake-based game engines
3D geometry format[30]CAD systems
[31]Archivebzip2

C

Ext.DescriptionUsed by
C-- language sourceSphinx C--
CC language source
Note that on case-sensitive platforms like Unix and with the gcc compiler the uppercase .C extension indicates a C++ source file.[32]		Watcom C/C++, Borland C/C++, gcc and other C compilers
CUnix file archiveCOMPACT
C++ language source
C++ language source
COMBOOT Executable (32-bit)SYSLINUX
[33]Cabinet archiveWindows 95 and later, many file archivers
[34]COBOL language source
COMBOOT Executable (incompatible with DOS COM files)SYSLINUX
C++ language source
ASP.NET class diagram file[14]
[35]Common Data Format
[36]Computable Document FormatMathematica
[37]Trainz Railroad Simulator Content Dispatcher PackTrainz Railroad Simulator
[38]Vector graphics format (drawinFCorelDraw
MIME type: chemical/x-cdxmlXML version of the ChemDraw Exchange format, CDX.[39]
[40]Security certificateMicrosoft Windows
[41][42]Computer Graphics Metafile vector graphicsA&L - HG - many
[43]Compiled Help FileMicrosoft Windows, Help Explorer Viewer
[44]ChordPro lead sheet (lyrics and chords)ChordPro and similar tools
Decrypted Nintendo 3DS ROM cartridgeNintendo 3DS
[45][46]Crystallographic Information FileRasMol, Jmol
[47]Java class fileJava
ooRexx class fileooRexx
Command Prompt batch fileMicrosoft Windows NT based operating systems
[48]executable programsCP/M-86 operating system
Chemical Markup Language, for interchange of chemical information.[49]
[50]Celestia ModelCelestia
[51]CNR IDLMITRE
3D object file format with normals (.noff, .cnoff)[52] NOFF is an acronym derived from Object File Format. Occasionally called CNOFF if color information is present.[53]
[54]COBOL language sourceGnuCOBOL
[55]Coefficient fileXilinx ISE
3D object file format (.off, .coff)[56] OFF is an acronym for Object File Format. Used for storing and exchanging 3D models. Occasionally called COFF if color information is present.[57]
DIMACS graph data format.[58]
DOS programDOS-
[14]ASP.NET precompiled stub file
Configuration file
[59]Compressed imageCartesian Perceptual Compression
cpio archive filecpio
[60]Control panel fileWindows 3.x
[54]COBOL source copybook file
[61]Raw image formatCanon digital cameras
Raw image formatCanon R series cameras
[62]CRAM index
Holds Spacecraft Assembly informationKerbal Space Program
[40]Security certificateMicrosoft Windows
[63]C# language source
[64][65]C# project fileMicrosoft Visual Studio
[66]Cascading style sheet
[67]Compiled Shader Object, extension of compiled HLSLHigh-Level Shading Language
[68]Comma Separated Values text file format (ASCII)
Used by electronic structure programs to store orbital or density values on a three-dimensional grid.[69]
same as .cub
Non-animated cursor (extended from ICO)Windows
C++ language source

D

Ext.DescriptionUsed by
DD Programming Language source fileDMD
DDirectory containing configuration files (informal standard)Unix
Direct Access Archive
COLLADA file
Data fileDigital Anchor
Extended from HTMLDarkPurpleOF's Website Extension
JSON Sticker Pack FileDarkPurpleOF's Website Importable
Dart source fileDart
AMPL data fileAMPL
LDraw (Sub)Part File, 3D ModelLDraw
DataRSNetWorx Project
Data file in special format or ASCII
Database fileClarion (programming language)
Norton Utilities disc image data. It saves Boot sector, part of FAT and root directory in image.DAT on same drive.Norton Utilities
Optical disc image (can be ISO9660, but not restricted to)cdrdao, burnatonce
Video CD MPEG stream
Windows registry hive (REG.DAT Windows 3.11; USER.DAT and SYSTEM.DAT Windows 95, 98, and ME; NTUSER.DAT Windows NT/2000/XP/7)Microsoft Windows
Dynamic sourceATS
Database fileDB Browser for SQLite
DarkBasic source code
Database Connection configuration fileAbInitio
Native format of the dBASE database management application.[70]
Debugger scriptDOS debug - Watcom debugger
Symbolic debugging informationMicrosoft C/C++
deb software packageDebian Linux and derivatives
digital elevation model (DEM) including GTOPO30 and USGSDEM. GTOPO30 is a distribution format for a global digital elevation model (DEM) with 30-arc-second grid spacing.[71] USGSDEM is the standard format for the distribution of terrain elevation data for the United States.[72]
CAD DrawingBentley Systems, MicroStation and Intergraph's Interactive Graphics Design System (IGDS) CAD programs
Digital Imaging and Communications in Medicine (DICOM) bitmapDICOM Software (XnView)
Data Interchange FormatVisicalc
Output from [diff] command - script for Patch command
Directory listing (ls format)Dired
DivX media format
Dynamic-link library is a shared library.Microsoft Windows or OS/2 operating system.
Apple Disk ImagemacOS (Disk Utility)
memory dump file (e.g. screen or memory)
Dimension model formatAdobe Dimension[73]
[74]Digital Negative, a-publicly available archival format for the raw files generated by digital camerasAt least 30 camera models from at least 10 manufacturers, and at least 200 software products
Redo recipes; usually written in sh, but may be written in a different language with a shebang.Redo[75]
[76][77][78]A Document, or an ASCII text file with text formatting codes in with the text; used by many word processorsMicrosoft Word and others
Microsoft Word Macro-Enabled DocumentMicrosoft Word
[79]Microsoft Word DocumentMicrosoft Word
[79]Microsoft Word document templateMicrosoft Word
[79]Office Open XML Text document templateMicrosoft Word
[80][81]Digital Picture Exchange
Dirac format video
[82]Celestia Deep Space Catalog fileCelestia
Stata database transport format.[83]Stata
[84]Document Type Definition
[85]Data version control yaml pointer into blob storage
Autodesk Design Web FormatDesign Review
[86]DrawingAutoCAD, IntelliCAD, PowerCAD, Drafix, DraftSight etc.
same as JDX and JCM.
[87]Drawing Interchange File Format vector graphicsAutoCAD, IntelliCAD, PowerCAD, etc.

E

Ext.DescriptionUsed by
EE language source codeE
EnCase Evidence File chunkEnCase Forensic Analysis Suite entity
ArcInfo interchange fileGIS software
2-dimensional vector graphics fileEditor included in JFire
A file format developed by ASTM International for storing point clouds and imagesMost software that enables viewing and/or editing of 3D point clouds
versions of DOS system files (AUTOEXEC.BAT, COMMAND.COM, CONFIG.SYS, WINBOOT.SYS, etc.) for an emergency boot diskWindows 98, ME
Source codeeC
Error-checking filedvdisaster
Ensoniq EPS disk imageAWAVE
European data formatMedical timeseries storage files
Extensible Firmware Interface
EIS Spectrum Analyser ProjectEIS Spectrum Analyser Archived 2010-03-29 at the Wayback Machine
Emacs Lisp source code fileEmacs
Byte-compiled Emacs Lisp codeEmacs
Executable and Linkable File EurekaLog File (contains details of an exception)Unix EurekaLog (https://www.eurekalog.com/)
Outlook Express Email MessageWindows Live Mail, Outlook Express, Microsoft Notepad
E language source code (maker)E
Microsoft Enhanced Metafile
Email conforming to RFC 5322;[88] Stationery TemplateEmail clients;Outlook Express
Microsoft Enhanced Metafile compressed with ZIPMicrosoft Office suite
Embedded OpenType
GUI wireframe/prototype projectPrikhi Pencil, Evolus Pencil
Award BIOS splash screenAward BIOS, XnView
Encapsulated PostScriptCorelDraw - PhotoStyler - PMView - Adobe Illustrator - Ventua Publisher
Electronic Publication (e-Reader format)Okular (Linux) - Apple Books - Sony Reader - Adobe Digital Editions - Calibre (LMW)
Europa Universalis 4 save game fileEuropa Universalis 4
Erlang source code file
ECMAScript 6 file
Data file of "esCAD pcb", PCB Pattern Layout Design SoftwareesCAD pcb provided by Electro-System
Data file of "esCAD sch", Drawing Schematics Diagram SoftwareesCAD sch provided by Electro-System
Windows Imaging FormatImageX, DISM, 7-Zip, wimlib
Electronic Theater Controls, Inc. theatrical lighting show control fileETC Eos platform software and consoles
event trace log fileMicrosoft[89][90]
Windows Event log fileMicrosoft Windows NT 4.0 - XP; Microsoft Event Viewer
Windows Event log file XML structuredMicrosoft Windows Vista, 7, 8; Microsoft Event Viewer
Elixir source code fileElixir programming language running on BEAM (Erlang virtual machine)[91]
Directly executable programDOS, OpenVMS, Microsoft Windows, Symbian or OS/2
Drawing File formatDrawing Express
Melco Embroidery FormatEmbroidermodder
OpenEXR raster image format (.exr).[56] Used in digital image manipulation for theatrical film production. EXR is an acronym for Extended Dynamic Range. Stores 16 bit per pixel IEEE HALF-precision floating-point color channels. Can optionally store 32-bit IEEE floating-point "Z" channel depth-buffer components, surface normal directions, or motion vectors.[92]
Elixir script fileInteractive Elixir (IEx) shell[93]

See also

References

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  3. ^ "Listing of All Formats"
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  5. ^ "What is a vector file?". adobe.com. Retrieved 2020-09-12.
  6. ^ Tom Erbe (1999). "AIFF-C Compression Types and Names". Archived 2006-06-20 at the Wayback Machine. Retrieved 2010-03-21.
  7. ^ "AIFF (.aif, .aiff, .aifc)"
  8. ^ Specification for Data Exchange Format for Additive Manufacturing
  9. ^ Specification of AMF on ISO web page
  10. ^ "AutomationML". AutomationML e. V. Retrieved 2020-09-13.
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  12. ^ Burner, Mike & Kale, Brewster (1996-09-15). "Arc File Format". Retrieved 2020-09-13.
  13. ^ "Gerber Format". ucamco.com. 2020-04-09. Retrieved 2020-09-13.
  14. ^ ASP.NET Web Project File Types
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  42. ^ ISO/IEC 8632
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  70. ^ "DBF (.dbf)"
  71. ^ "GTOPO30"
  72. ^ "USGSDEM (.dem)"
  73. ^ Adobe Dimension User Guide
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  75. ^ [1]
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