List of filename extensions (A–E)

From Wikipedia, the free encyclopedia

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


Ext. Description Used by
A Archive file ar (Unix)
AAC Advanced Audio Coding file iOS, Nintendo DSi, Nintendo 3DS, YouTube Music
ACCDB[1] Microsoft Access Database Microsoft Access Database (Open XML)
ACCFT[2] Microsoft Access Data Type Template Microsoft Access
ADT Abrechnungsdatentransfer, an xDT application Healthcare providers in Germany
ADX Document Archetype Designer
ADZ Amiga Disk Zipped (See Amiga Disk File) GZip
AGDA Agda (programming language) source file Agda typechecker/compiler
AGR ArcView ASCII grid
AHK AutoHotkey script file AutoHotkey
AI[3] Adobe Illustrator Artwork Adobe Illustrator
AIFF[4] Audio Interchange File Format
AIFC[4] Compressed Audio Interchange File Format
AIO APL programming language file transfer format file
AMF[5][6] Additive Manufacturing File Format Computer Aided Design Software
AMG System image file ACTOR
AML[7] AutomationML AutomationML Group
AMLX[7] Compressed and packed AutomationML file AutomationML Group
AMPL AMPL source code file AMPL
AMR Adaptive Multi-Rate audio
AMV Actions Media Video
ANI[8] Animation cursors for Win Win95 - WinNT
ANN Annotations of old Windows Help file Windows 3.0 - XP
APE Monkey's Audio (Lossless) audio media players
APK Android application package Android
APK Alpine Linux Package Alpine Linux and derivatives
ARC[9] ARC (file format)
ART[10] Gerber format Cadence Allegro, EAGLE
ASAX[11] ASP.NET global application file
ASCX[11] ASP.NET User Control
ASF[12] Advanced Streaming Format (Compressed Windows audio/video) Microsoft Corporation
ASHX[11] ASP.NET handler file
ASM Assembler language source TASM, MASM, NASM, FASM
ASPX Active server page extended file Microsoft Corporation
ASX[13] Advanced Stream Redirector file, redirects to an ASF file (see ASF) Microsoft Corporation
ATG[14] Coco/R LL(1) formal grammar Coco/R
AT3[15] Atrac 3 Sound/music file All Sony devices and programs with the Atrac 3+ specification
AVI[16][17] Audio Video Interleave Video for Windows
AWK AWK script/program awk, GNU Awk, mawk, nawk, MKS AWK, Awka (compiler)
AX DirectShow Filter Microsoft Corporation (Video Players)
AXF[18] lightweight geodatabase ESRI ArcPad


Ext. Description Used by
B BASIC language source
B bc arbitrary precision calculator language file Unix bc tool
BAK backup various
BAR Broker Archive. Compressed file containing number of other files for deployment.[19] IBM App Connect
BAS BASIC language source QuickBASIC - GW-BASIC - FreeBASIC - others
BAT Batch file MS-DOS, RT-11
BDF Glyph Bitmap Distribution Format, a format used to store bitmap fonts. Adobe
BDT Behandlungsdatentransfer, an xDT application Healthcare providers in Germany
BEAM Executable bytecode file in fat binary format BEAM (Erlang virtual machine)[20]
BIN binary file Every OS
BM3 UIQ3 Phone backup
BMP[21] OS/2 or Win graphics format (BitMap Picture) QPeg - CorelDraw - PC Paintbrush - many
BPS WPS backup file[22] Microsoft Word, Microsoft Works
BZ2[23] Archive bzip2
BLEND Blender project file Blender


Ext. Description Used by
C-- C-- language source Sphinx C--
C C language source

Note that on case-sensitive platforms like Unix and with the gcc compiler the uppercase .C extension indicates a C++ source file.[24]

Watcom C/C++, Borland C/C++, gcc and other C compilers
C Unix file archive COMPACT
C++ C++ language source
CPP C++ language source
C32 COMBOOT Executable (32-bit) SYSLINUX
CAB[25] Cabinet archive Windows 95 and later, many file archivers
CBT COMBOOT Executable (incompatible with DOS COM files) SYSLINUX
CC C++ language source
CD ASP.NET class diagram file[11]
CDF[26] Common Data Format
CDF[27] Computable Document Format Mathematica
CDP[28] Trainz Railroad Simulator Content Dispatcher Pack Trainz Railroad Simulator
CDR[29] Vector graphics format (drawinF CorelDraw
CER[30] Security certificate Microsoft Windows
CGM[31][32] Computer Graphics Metafile vector graphics A&L - HG - many
CHM[33] Compiled Help File Microsoft Windows, Help Explorer Viewer
CHO[34] ChordPro lead sheet (lyrics and chords) ChordPro and similar tools
CIA Decrypted Nintendo 3DS ROM cartridge Nintendo 3DS
CIF[35][36] Crystallographic Information File RasMol, Jmol
CLASS[37] Java class file Java
CMD Command Prompt batch file Microsoft Windows NT based operating systems
CMD[38] executable programs CP/M-86 operating system
CMOD[39] Celestia Model Celestia
COE[41] Coefficient file Xilinx ISE
COM DOS program DOS-
COMPILE[11] ASP.NET precompiled stub file
CPC[42] Compressed image Cartesian Perceptual Compression
CPL[43] Control panel file Windows 3.x
CR2[44] Raw image format Canon digital cameras
CRAI[45] CRAM index
CRT[30] Security certificate Microsoft Windows
CS[46] C# language source
CSPROJ[47][48] C# project file Microsoft Visual Studio
CSS[49] Cascading style sheet
CSV[50] Comma Separated Values text file format (ASCII)
CUR Non-animated cursor (extended from ICO) Windows


Ext. Description Used by
D D Programming Language source file DMD
D Directory containing configuration files (informal standard) Unix
DAA Direct Access Archive
DAF Data file Digital Anchor
DART Dart (programming language) source file
DAT AMPL data file AMPL
DAT LDraw (Sub)Part File, 3D Model LDraw
DAT Data RSNetWorx Project
DAT Data file in special format or ASCII
DAT Database file Clarion (programming language)
DAT Norton Utilities disc image data. It saves Boot sector, part of FAT and root directory in image.DAT on same drive. Norton Utilities
DAT Optical disc image (can be ISO9660, but not restricted to) cdrdao, burnatonce
DAT Video CD MPEG stream
DAT 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
DATS Dynamic source ATS
DBA DarkBasic source code
DBC Database Connection configuration file AbInitio
DBG Debugger script DOS debug - Watcom debugger
DBG Symbolic debugging information Microsoft C/C++
DICOM Digital Imaging and Communications in Medicine (DICOM) bitmap DICOM Software (XnView)
DIF Data Interchange Format Visicalc
DIF Output from [diff] command - script for Patch command
DIRED Directory listing (ls format) Dired
DIVX DivX media format
DMG Apple Disk Image macOS (Disk Utility),
DMP memory dump file (e.g. screen or memory)
DN Dimension model format Adobe Dimension[51]
DNG[52] Digital Negative, a-publicly available archival format for the raw files generated by digital cameras At least 30 camera models from at least 10 manufacturers, and at least 200 software products
DOC[53][54][55] A Document, or an ASCII text file with text formatting codes in with the text; used by many word processors Microsoft Word and others
DOCM Microsoft Word Macro-Enabled Document Microsoft Word
DOCX[56] Microsoft Word Document Microsoft Word
DOT[56] Microsoft Word document template Microsoft Word
DOTX[56] Office Open XML Text document template Microsoft Word
DPX[57][58] Digital Picture Exchange
DRC Dirac format video
DSC[59] Celestia Deep Space Catalog file Celestia
DTD[60] Document Type Definition
DVC[61] Data version control yaml pointer into blob storage
DWF Autodesk Design Web Format Design Review
DWG[62] Drawing AutoCAD, IntelliCAD, PowerCAD, Drafix, DraftSight etc.
DXF[63] Drawing Interchange File Format vector graphics AutoCAD, IntelliCAD, PowerCAD, etc.


Ext. Description Used by
E E language source code E
E## EnCase Evidence File chunk EnCase Forensic Analysis Suite entity
E00 ArcInfo interchange file GIS software
E2D 2-dimensional vector graphics file Editor included in JFire
e57 A file format developed by ASTM International for storing point clouds and images Most software that enables viewing and/or editing of 3D point clouds
EBD versions of DOS system files (AUTOEXEC.BAT, COMMAND.COM, CONFIG.SYS, WINBOOT.SYS, etc.) for an emergency boot disk Windows 98, ME
EC Source code eC
ECC Error-checking file dvdisaster
EDE Ensoniq EPS disk image AWAVE
EDF European data format Medical timeseries storage files
EFI Extensible Firmware Interface
EIS EIS Spectrum Analyser Project EIS Spectrum Analyser
EL Emacs Lisp source code file Emacs
ELC Byte-compiled Emacs Lisp code Emacs
ELF Executable and Linkable File Unix
EMAIL Outlook Express Email Message Windows Live Mail, Outlook Express, Microsoft Notepad
EMAKER E language source code (maker) E
EMF Microsoft Enhanced Metafile
EML Email conforming to RFC 5322;[64] Stationery Template Email clients;Outlook Express
EMZ Microsoft Enhanced Metafile compressed with ZIP Microsoft Office suite
EOT Embedded OpenType
EP GUI wireframe/prototype project Prikhi Pencil, Evolus Pencil
EPA Award BIOS splash screen Award BIOS, XnView
EPS Encapsulated PostScript CorelDraw - PhotoStyler - PMView - Adobe Illustrator - Ventua Publisher
EPUB Electronic Publication (e-Reader format) Okular (Linux) - Apple Books - Sony Reader - Adobe Digital Editions - Calibre (LMW)
EU4 Europa Universalis 4 save game file Europa Universalis 4
ERL Erlang source code file
ES6 ECMAScript 6 file
ESCPCB Data file of "esCAD pcb", PCB Pattern Layout Design Software esCAD pcb provided by Electro-System
ESCSCH Data file of "esCAD sch", Drawing Schematics Diagram Software esCAD sch provided by Electro-System
ESD Windows Imaging Format ImageX, DISM, 7-Zip, wimlib
ETL event trace log file Microsoft[65][66]
EVT Windows Event log file Microsoft Windows NT 4.0 - XP; Microsoft Event Viewer
EVTX Windows Event log file XML structured Microsoft Windows Vista, 7, 8; Microsoft Event Viewer
EX Elixir source code file Elixir programming language running on BEAM (Erlang virtual machine)[67]
EXE Directly executable program DOS, OpenVMS, Microsoft Windows, Symbian or OS/2
EXP Drawing File format Drawing Express
EXP Melco Embroidery Format Embroidermodder
EXS Elixir script file Interactive Elixir (IEx) shell[68]

See also[edit]


  1. ^ "Which Access file format should I use?". Retrieved 2020-09-13.
  2. ^ "Save and reuse database design elements". Retrieved 29 October 2015.
  3. ^ "What is a vector file?". Retrieved 2020-09-12.
  4. ^ a b Tom Erbe (1999). "AIFF-C Compression Types and Names". Archived from the original on 2006-06-20. Retrieved 2010-03-21.
  5. ^ Specification for Data Exchange Format for Additive Manufacturing
  6. ^ Specification of AMF on ISO web page
  7. ^ a b "AutomationML". AutomationML e. V. Retrieved 2020-09-13.
  8. ^ "About animated cursors". Retrieved 2020-09-14.
  9. ^ Burner, Mike; Kale, Brewster (1996-09-15). "Arc File Format". Retrieved 2020-09-13.
  10. ^ "Gerber Format". 2020-04-09. Retrieved 2020-09-13.
  11. ^ a b c d e ASP.NET Web Project File Types
  12. ^ "Overview of the ASF format". 2018-05-31. Retrieved 2020-09-12.
  13. ^ "ASX Element". 2018-05-31. Retrieved 2020-09-14.
  14. ^ "Coco/R own DSL grammar".
  15. ^ "ATRAC Developer's Interview". Retrieved 2020-09-12.
  16. ^ "AVI File Format with OpenDML Extensions, Version 1.02". 2016-03-09. Retrieved 2019-09-01.
  17. ^ stevewhims. "AVI RIFF File Reference - Windows applications". Retrieved 2019-09-01.
  18. ^ "The ArcPad Team Blog: What is an ArcPad AXF?".
  19. ^ "Deploying integration solutions". Retrieved 2021-05-18.
  20. ^ "The Erlang Runtime System". Retrieved 2018-05-07.
  21. ^ "Bitmap Storage". 2018-05-31. Retrieved 2020-09-12.
  22. ^ "BPS File Extension - What is a .bps file and how do I open it?". Retrieved 2018-10-12.
  23. ^ "BZIP2 Format Specification" (PDF). GitHub. 27 February 2022.
  24. ^ "Overall Options - Using the GNU Compiler Collection (GCC)". Retrieved 2020-06-27.
  25. ^ "Cabinet Files". 2018-05-31. Retrieved 2020-09-13.
  26. ^ "What is Common Data Format (CDF)?". Retrieved 2020-09-13.
  27. ^ "Computable Document Format". Retrieved 2020-09-12.
  28. ^ "CDP File - What is it and how do I open it?". Retrieved 2022-10-28.
  29. ^ "Trying to Open a .CDR File?". Retrieved 2020-09-12.
  30. ^ a b "Certificate extensions explained". Retrieved 2020-09-12.
  31. ^ IANA Image Media Types
  32. ^ ISO/IEC 8632
  33. ^ "Create a Help Project". 2018-05-31. Retrieved 2020-09-12.
  34. ^ "Welcome to ChordPro!". Retrieved 2020-09-12.
  35. ^ Hall SR, Allen FH, Brown ID (1991). "The Crystallographic Information File (CIF): a new standard archive file for crystallography". Acta Crystallographica Section A. 47 (6): 655–685. doi:10.1107/S010876739101067X.
  36. ^ Brown ID, McMahon B (2002). "CIF: the computer language of crystallography". Acta Crystallographica Section B: Structural Science. 58 (Pt 3 Pt 1): 317–24. doi:10.1107/s0108768102003464. PMID 12037350.
  37. ^ "The class File Format". Retrieved 2020-09-12.
  38. ^ Elliott, John C. "CP/M-86 executables (.CMD)". Archived from the original on 2016-11-14. Retrieved 2016-08-29.
  39. ^ "Celestia's CMOD model format". Retrieved 2020-09-12.
  40. ^ "MITRE's Combat Net Radio Initialization File". Retrieved 2020-11-30.
  41. ^ "COE File Syntax". 2009.
  42. ^ "Technical Overview of Cartesian Perceptual Compression". 1999. Retrieved 2020-09-13.
  43. ^ "Description of Control Panel (.cpl) Files". 2020-08-19. Retrieved 2020-09-12.
  44. ^ "Understanding What is stored in a Canon RAW .CR2 file, How and Why". Retrieved 2020-09-12.
  45. ^ Hsi-Yang Fritz, Markus; Leinonen, Rasko; Cochrane, Guy; Birney, Ewan (May 2011). "Efficient storage of high throughput DNA sequencing data using reference-based compression". Genome Research. 21 (5): 734–740. doi:10.1101/gr.114819.110. ISSN 1549-5469. PMC 3083090. PMID 21245279.
  46. ^ "Introduction to projects and solutions". 2020-11-17. Retrieved 2021-05-06.
  47. ^ "Additions to the csproj format for .NET Core". 2019-04-28. Retrieved 2020-09-12.
  48. ^ "Understanding the project file". 2012-05-04.
  49. ^ "Cascading Style Sheets home page". Retrieved 2020-09-12.
  50. ^ Shafranovich, Y. (October 2005). Common Format and MIME Type for CSV Files. IETF. p. 1. doi:10.17487/RFC4180. RFC 4180.
  51. ^ Adobe Dimension User Guide
  52. ^ "Digital Negative (DNG)". Adobe Systems Incorporated. Retrieved 2018-07-30.
  53. ^ Microsoft Office Binary (doc, xls, ppt) File Formats, 2008-02-15, archived from the original on 2008-02-18
  54. ^ "Microsoft Office Word 97 - 2007 Binary File Format Specification (*.doc)" (PDF). Microsoft Corporation. 2008.
  55. ^ MS-DOC: Word (.doc) Binary File Format, 2019-11-19, retrieved 2020-02-25
  56. ^ a b c "Word Extensions to the Office Open XML (.docx) File Format". 2020-08-18. Retrieved 2020-08-29.
  57. ^ ST 268-1:2014 - SMPTE Standard - File Format for Digital Moving-Picture Exchange (DPX). SMPTE. doi:10.5594/SMPTE.ST268-1.2014. ISBN 978-1-68303-083-6.
  58. ^ ST 268-2:2018 - SMPTE Standard - Digital Moving-Picture Exchange (DPX) – Format Extensions for High Dynamic Range and Wide Color Gamut. SMPTE. doi:10.5594/SMPTE.ST268-2.2018. ISBN 978-1-68303-161-1.
  59. ^ "DSC Parameters recognized by Celestia v1.4.1 (and later)". Retrieved 2020-09-13.
  60. ^ "Extensible Markup Language (XML) 1.0". (5 ed.). 2008-11-26. Retrieved 2020-09-13.
  61. ^ "Data Version Control".
  62. ^ "Open Design Specification for .dwg Files" (PDF). Retrieved 2020-09-13.
  63. ^ "DXF Reference" (PDF). February 2011. Retrieved 2020-09-13.
  64. ^ ".EML File Extension". Archived from the original on 2021-08-12. Retrieved 2022-01-10.
  65. ^ "Windows Event Trace Log Sink". Microsoft TechNet. Microsoft. 2005-06-20. Retrieved 2017-02-08. The Event Trace Sink provided with the Microsoft Enterprise Instrumentation Framework (EIF) produces event trace log (.etl) files [...].
  66. ^ Compare: Rea, Sara Morgan (2005). Building Intelligent .NET Applications: Agents, Data Mining, Rule-based Systems, and Speech Processing. Addison-Wesley Microsoft Technology Series. Addison Wesley. p. 41. ISBN 9780321246264. Retrieved 2017-02-08. Each call is logged to the Windows Event Trace Log and stored in a log file with an .etl (event log tracing) extension.
  67. ^ "Modules and functions". Retrieved 2018-05-07.
  68. ^ "Erlang/Elixir Syntax: A Crash Course". Retrieved 2018-05-07.

External links[edit]