List of filename extensions (A–E)
This alphabetical list of filename extensions contains extensions of notable file formats used by multiple notable applications or services.
A
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
ACO
Adobe color palette format (.aco)[3]
Adobe Photoshop [4]
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 [5]
Adobe Illustrator Artwork
Adobe Illustrator
AIFF [6]
Audio Interchange File Format
professional audio processing applications and on Macintosh[7]
AIFC [6]
Compressed Audio Interchange File Format
AIO
APL programming language file transfer format file
AMF [8] [9]
Additive Manufacturing File Format
Computer Aided Design Software
AMG
System image file
ACTOR
AML [10]
AutomationML
AutomationML Group
AMLX [10]
Compressed and packed AutomationML file
AutomationML Group
AMPL
AMPL source code file
AMPL
AMR
Adaptive Multi-Rate audio
AMV
Actions Media Video
ANI [11]
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 [12]
ARC (file format)
ART [13]
Gerber format
Cadence Allegro, EAGLE
ASAX [14]
ASP.NET global application file
ASCX [14]
ASP.NET User Control
ASF [15]
Advanced Streaming Format (Compressed Windows audio/video)
Microsoft Corporation
ASHX [14]
ASP.NET handler file
ASM
Assembler language source
TASM , MASM , NASM , FASM
ASPX
Active server page extended file
Microsoft Corporation
ASX [16]
Advanced Stream Redirector file, redirects to an ASF file (see ASF)
Microsoft Corporation
ATG [17]
Coco/R LL(1) formal grammar
Coco/R
AT3 [18]
Atrac 3 Sound/music file
All Sony devices and programs with the Atrac 3+ specification
AU
audio file[19]
AVI [20] [21]
Audio Video Interleave
Video for Windows
AVIF
AV1 Image File Format
AWK
AWK script/program
awk, GNU Awk, mawk, nawk, MKS AWK, Awka (compiler)
AX
DirectShow Filter
Microsoft Corporation (Video Players)
AXF [22]
lightweight geodatabase
ESRI ArcPad
B
C
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.[31]
Watcom C/C++, Borland C/C++, gcc and other C compilers
C
Unix file archive
COMPACT
C++
C++ language source
CPP
C++ language source
Config
Configuration file
C32
COMBOOT Executable (32-bit )
SYSLINUX
CAB [32]
Cabinet archive
Windows 95 and later, many file archivers
CBL [33]
COBOL language source
CBT
COMBOOT Executable (incompatible with DOS COM files)
SYSLINUX
CC
C++ language source
CD
ASP.NET class diagram file[14]
CDF [34]
Common Data Format
CDF [35]
Computable Document Format
Mathematica
CDP[36]
Trainz Railroad Simulator Content Dispatcher Pack
Trainz Railroad Simulator
CDR [37]
Vector graphics format (drawinF
CorelDraw
CDXML
MIME type: chemical/x-cdxmlXML version of the ChemDraw Exchange format, CDX.[38]
CER [39]
Security certificate
Microsoft Windows
CGM [40] [41]
Computer Graphics Metafile vector graphics
A&L - HG - many
CHM [42]
Compiled Help File
Microsoft Windows , Help Explorer Viewer
CHO [43]
ChordPro lead sheet (lyrics and chords)
ChordPro and similar tools
CIA
Decrypted Nintendo 3DS ROM cartridge
Nintendo 3DS
CIF [44] [45]
Crystallographic Information File
RasMol , Jmol
CLASS [46]
Java class file
Java
CLS
ooRexx class file
ooRexx
CMD
Command Prompt batch file
Microsoft Windows NT based operating systems
CMD [47]
executable programs
CP/M-86 operating system
CML
Chemical Markup Language, for interchange of chemical information.[48]
CMOD [49]
Celestia Model
Celestia
CN1 [50]
CNR IDL
MITRE
CNOFF
3D object file format with normals (.noff, .cnoff)[51] NOFF is an acronym derived from Object File Format. Occasionally called CNOFF if color information is present.[52]
COB [53]
COBOL language source
GnuCOBOL
COE [54]
Coefficient file
Xilinx ISE
COFF
3D object file format (.off, .coff)[55] OFF is an acronym for Object File Format. Used for storing and exchanging 3D models. Occasionally called COFF if color information is present.[56]
COL
DIMACS graph data format.[57]
COM
DOS program
DOS -
COMPILE [14]
ASP.NET precompiled stub file
CPC [58]
Compressed image
Cartesian Perceptual Compression
CPIO
cpio archive file
cpio
CPL [59]
Control panel file
Windows 3.x
CPY [53]
COBOL source copybook file
CR2 [60]
Raw image format
Canon digital cameras
CR3[61]
Raw image format
Canon R series cameras
CRAI [62]
CRAM index
CRAFT
Holds Spacecraft Assembly information
Kerbal Space Program
CRT [39]
Security certificate
Microsoft Windows
CS [63]
C# language source
CSPROJ [64] [65]
C# project file
Microsoft Visual Studio
CSS [66]
Cascading style sheet
CSO [67]
Compiled Shader Object, extension of compiled HLSL
High-Level Shading Language
CSV [68]
Comma Separated Values text file format (ASCII)
CUB
Used by electronic structure programs to store orbital or density values on a three-dimensional grid.[69]
CUBE
same as .cub
CUR
Non-animated cursor (extended from ICO )
Windows
D
Ext.
Description
Used by
D
D Programming Language source file
DMD
D
Directory containing configuration files (informal standard)
Unix
DAA
Direct Access Archive
DAE
COLLADA file
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
DBF
Native format of the dBASE database management application.[70]
DBG
Debugger script
DOS debug - Watcom debugger
DBG
Symbolic debugging information
Microsoft C/C++
DEB
deb software package
Debian Linux and derivatives
DEM
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]
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 [73]
DNG [74]
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 [75] [76] [77]
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 [78]
Microsoft Word Document
Microsoft Word
DOT [78]
Microsoft Word document template
Microsoft Word
DOTX [78]
Office Open XML Text document template
Microsoft Word
DPX [79] [80]
Digital Picture Exchange
DRC
Dirac format video
DSC [81]
Celestia Deep Space Catalog file
Celestia
DTA
Stata database transport format.[82]
Stata
DTD [83]
Document Type Definition
DVC [84]
Data version control yaml pointer into blob storage
DWF
Autodesk Design Web Format
Design Review
DWG [85]
Drawing
AutoCAD , IntelliCAD , PowerCAD, Drafix, DraftSight etc.
DX
same as JDX and JCM.
DXF [86]
Drawing Interchange File Format vector graphics
AutoCAD , IntelliCAD , PowerCAD, etc.
E
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 Archived 2010-03-29 at the Wayback Machine
EL
Emacs Lisp source code file
Emacs
ELC
Byte-compiled Emacs Lisp code
Emacs
ELF
Executable and Linkable File
EurekaLog File (contains details of an exception)
Unix
EurekaLog (https://www.eurekalog.com/ )
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 ;[87] 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[88] [89]
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) [90]
EXE
Directly executable program
DOS , OpenVMS , Microsoft Windows , Symbian or OS/2
EXP
Drawing File format
Drawing Express
EXP
Melco Embroidery Format
Embroidermodder
EXR
OpenEXR raster image format (.exr).[55] 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.[91]
EXS
Elixir script file
Interactive Elixir (IEx) shell[92]
See also
References
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^
"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 [...].
^
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External links