Alphabetical list of file formats (A–E)

This alphabetical list of filename extensions contains standard extensions associated with computer files.

Symbols

Ext.	Description	Used by
###	Temporary file	program-dependent format
#24	Printer data file for 24 pin matrix printer	LocoScript
#IB	Printer data file	LocoScript
#nn	Part of file image	Long
#SC	Printer data file	LocoScript
#ST	Standard mode printer definitions	LocoScript
$$$	OS/2 archive file (i.e. archives.$$$, keys.$$$)	OS/2
$$$	Temporary file
$?	ZX Spectrum file in HOBETA format
$00	Pipe file	DOS
$DB	Temporary file	dBASE IV
$ED	Editor temporary file	MS C
$O1	Pipe file	DOS
$VM	Virtual manager temporary file	Windows 3.x
)2(	LHA archiver temporary file	LHA
??$	Backup file	P-CAD
??_	Microsoft packed file	Expand
?DK	Disk image	Loaddskf.exe
?UT	Nonpacked FTN mail (? - flavor)	FTN software
!ut	Unfinished µTorrent download	µTorrent
___	Adinf table	Adinf
EX_	Compressed executable file	Note: EX could be any first two characters in a file extension (e.g. BM_ for compressed bitmap (BMP), DL_ for compressed library, etc.) Files compressed using this method have been in use on Microsoft software CDs and floppies since around 1995.
?Q?	Squeeze for CP/M and MS-DOS
~$~	Temporary file	1st Reader
~??	Old Backup files (.MNU to .~MN)	Resource Workshop (Borland Delphi)
~H	Cardfile heap	AZZ Cardfile
μ	Metrowerks Codewarrior project
Π	THINK C project
@@1, @@2, etc.	Hidownload temporary file	Hidownload

Numbers

Ext.	Description	Used by
0	Compressed harddisk data	DoubleSpace
0B	Printer font with lineDraw extended character set	PageMaker
1337	Kiwi's RTCoD File Format	Se7ensins & Teh1337
001, 002, ...	Split parts of a single whole file	FFSJ, HJSplit, JJSplit, split (Unix) (when using numeric suffixes)
1	Fax	many
1	Roff/nroff/troff/groff source for manual page	cawf2.zip
123	Spreadsheet	Lotus 1-2-3 version 9 and version 97
15U	Printer font with PI font set	PageMaker
16	SYSLINUX Splash Screen Graphic	SYSLINUX, XnView
1ST	Usually README.1ST text file
1TX	1toX Logipole file
2GR	286 Grabber File	Win
301	Fax	Super FAX 2000 - Fax-Mail 96
386	Intel 80386 processor driver	Windows 3.x
386	Windows virtual device driver	Win
3DMF	QuickDraw 3D Metafile	QuickDraw
3DS	3D Studio Graphics format	3D Studio
3DT	Database in which the meta-data of a 3D Topicscape is held	3D Topicscape
3DV	3-D wireframe graphics by Oscar Garcia	3dv wireframe viewer
3FX	Effect	CorelChart
3GA	Mobile Phone Audio (Samsung)
3GP	Mobile Phone Video
3GR	386 Grabber File	Win
3T4	Binary file converter to ASCII	Util3
4C$	Datafile	4Cast/2
4MD	Musical file
4SW	4DOS Swap File	4DOS
4TH	FORTH source code file	ForthCMP - LMI Forth
555	16 bit per pixel image file format (5bit per component)	Sierra Entertainment
602	Text (fairly simple format, plain text with binary control commands embedded within text lines and special formatting commands on dedicated lines)	Text602 text processor by Software602
668	Music (the mixing is always at 12048 Hz)
669	Music (8 channels)	The 669 Composer
6CM	Music (6 Channel Module)	Triton FastTracker
75	75×75 dpi display font	Ventura Publisher
7z	A compressed archive file format that supports several different data compression, encryption and pre-processing algorithms	7-Zip
8	A86 assembler source code file
85	85×85 dpi display font	Ventura Publisher
8BF	Adobe Photoshop compatibile filters/plugins
890	ScanTitling subtitle files
8CM	Music (8 Channel Module)	Triton FastTracker
8M	Printer font with Math 8 extended character set	PageMaker
8U	Printer font with Roman 8 extended character set	PageMaker
83p	Executable program for TI-83 Plus Graphing Calculator	TI Connect
89p	Executable program for TI-89/89 Titanium Graphing Calculator	TI Connect
8xp	Executable program for TI-83/84 Plus Graphing Calculator	TI Connect
91	91×91 dpi display font	Ventura Publisher
96	96×96 dpi display font	Ventura Publisher

A

Ext.	Description	Used by
A	ADA source code file
A	Library	Unix
A##	AlZip Compressed Files' pieces
A11	Graphics AIIM image file
A80	Assembler language source for 8080
AA, AB, ...	Split parts of a single whole file	split (Unix)
AAC	Advanced Audio Coding, a standardized, lossy compression and encoding scheme for digital audio
AAF	AutoPatcher file
AAF	Advanced Authoring Format, an advanced media wrapper file for professional applications
AAS	Animation Play Script	AAPlay
AB6	Datafile	ABStat
AB8	Datafile	ABStat
ABC	Alembic - 3D geometry / models	Many Computer Graphics tools, see Alembic (Computer Graphics) for a list.
ABC	Document	ABC FlowCharter 1.0
ABP	Data	ABComp compressed
ABP	AVS Barcode Profile	AVS Barcode Source
ABF	Adobe Binary Screen Font	Adobe Systems Software
ABK	Automatic backup file	CorelDRAW
ABM	Image PALS album file
ABM	Album file (various programs)
ABR	Adobe Brush file for PhotoShop	PhotoShop
ABS	Abstracts (info file)
ABS	Data file	Abscissa
AC	Project backup	Audit Command Language (ACL)
ACA	Project	Project Manager Workbench
ACB	Archive	ACB
ACB	see ACMB
ACC	Program (DR-DOS - ViewMax)	GEM / resident
ACCDA	Data	Microsoft Access Database Wizard (Open XML)
ACCDB	Data	Microsoft Access Database (Open XML)
ACCDE	Data	Microsoft Access Database Wizard (Open XML)
ACCDT	Data	Microsoft Access Database Template (Open XML)
ACCDU	Data	Microsoft Access Database Wizard (Open XML)
ACE	Archive	ACE
ACF	Adobe Custom Filter for PhotoShop	PhotoShop
ACL	Project	Audit Command Language (ACL)
ACL	AutoCorrect List	Microsoft Office
ACM	Audio Compression Module add-on	Win
ACMB	Graphics file
ACO	Adobe Color Palette
ACT	ACTOR source code file	ACTOR
ACT	Animations Works Actor (Graphics cell)	Animation Works
ACT	FoxDoc Action Diagrams	FoxPro
ACT	Presentation	Action!
AD	AfterDark screensaver module	AfterDark
AD2	ADPCM 2-bit compressed voice file	ZFAX
AD3	ADPCM 3-bit compressed voice file	ZFAX
ADA	Ada source code file
ADB	Ada Package Body
ADC	Bitmap graphics (16 colors)	Scanstudio
ADC	Dictionary	Lingvo
ADD	OS/2 adapter device driver
ADF	Amiga Disk File	unADF, UAE, WinUAE etc...
ADG	Data	ADG 3D Scene
ADI	Graphics file	AutoCAD
ADI	Database Index File	Advantage Database Server
ADICHT	LabChart data acquisition file	ADInstruments
ADL	MCA adapter description library	QEMM
ADM	After Dark support file	AfterDark
ADM	ADEM file format	ADEM
ADI	Database Memo File	Advantage Database Server
ADN	Add-in	Lotus 1-2-3
ADR	After Dark support file	AfterDark
ADS	Ada Package Specification
ADT	WoW geographical map location file	Blizzard Entertainment games (various)
ADT	Datafile for cardfile application	HP NewWave
ADT	Dictionary	Lingvo
ADT	Fax	AdTech
ADI	Database Table	Advantage Database Server
ADV	GUS device driver	Gf166.com
ADX	Document	Archetype Designer
ADZ	Amiga Disk Zipped (See Amiga Disk File)	GZip
AEP	After Effects Project File	Adobe After Effects
AES	File encrypted using the Advanced Encryption Standard (AES)	AES Crypt (Windows, Mac, Linux, Java) and Crypt4All (Android)
AF2	Flowchart	ABC FlowCharter 2.0
AF3	Flowchart	ABC FlowCharter 3.0
AFI	Truevision bitmap graphics
AFL	Font file (for Always)	Lotus 1-2-3
AFM	Datafile for cardfile application	HP NewWave
AFM	Type 1 font metric ASCII data for font installer	ATM - many
AFP	Shape palette	ABC FlowCharter
AFT	Template	ABC FlowCharter 3.0
AFW	Workplace	ABC FlowCharter 3.0
AGR	ArcView ASCII grid
AHK	AutoHotkey script file	AutoHotkey
AI	Vector graphics file	Adobe Illustrator
AIF	see AIFF
AIFC	Audio Interchange File Format with Compression
AIFF	Audio Interchange File Format	Convert (c) Villena
AiM	Asm Text Mode Image File	The Ultimate Draw
AIN	Archive	AIN
AIN	Job schedule	AutoIntern
AIO	APL programming language file transfer format file
AIR	Adobe AIR installation package	The Adobe AIR runtime environment
AIS	Array of Intensity Samples graphics file	Xerox
AIX	Datafile for cardfile application	HP NewWave
AKM	"Akai Multitimbral" sample information file	Akai S5000 and S6000 hardware samplers (MS-DOS-based) and compatible software samplers
AKP	"Akai Program" sample information file	Akai S5000 and S6000 hardware samplers (MS-DOS-based) and compatible software samplers
ALC	Molecular coordinates	Alchemy, RasMol
ALG	Activity Log	ARCSOLO
ALE	Avid Log Exchange (used in film & video editing)	Avid
ALL	Arts & Letters symbol and font files	Arts & Letters
ALL	Filelist w/ all files	FRQView
ALL	Format file for working pages	Always
ALL	General printer information	WordPerfect for Win
ALO	Almanac support file
ALT	Menu file	WordPerfect Library
ALZ	AlZip Compressed Files
AMD	Maxum chromatograph offline database	Siemens Maxum Chromatograph
AMF	Music (Advanced Module Format)	DMP
AMG	Archive	AMGC
AMG	System image file	ACTOR
AML	AutomationML	AutomationML Group
AMR	Audio format for mobile phones (Nokia, SonyEricsson)
AMS	Adobe Monitor Setup calibration file	PhotoShop
AMS	Music format
ANI	Animation cursors for Win	Win95 - WinNT
ANI	Animation	IconAuthor
ANM	Animation	Deluxe Paint Animator
ANIM	Trainz Animation specification file, for example a steam locomotive's connecting rod movements, or water movement on a river or lake motion. (Obsolescent)	Trainz/Auran JET files
ANN	Help Annotations	Windows 3.x
Ann	Multi volume ARJ archive	ARJ
ANS	ANSI character graphics (animation) file	ANSView
ANS	ASCII text ANSI character set	NewWave Write
AOL	America On-line for Windows DLL	Win
AOS	Add-On Software	Nokia 9000
AP	Archive	WHAP
AP	Datafile	Datalex EntryPoint 90
APC	Printer driver	Lotus 1-2-3
APD	Printer driver	Lotus 1-2-3
APE	Monkey's Audio (Lossless)	audio media players
APF	Printer driver	Lotus 1-2-3
API	Adobe Printer Ink file for PhotoShop	PhotoShop
API	Passed parameter file	1st Reader
API	Printer driver	Lotus 1-2-3
APK	Android Application	Android
APL	APL work space format file
APL	Support module used by Manugraphics APL products
APL	EV-Dos Application File
APM	Authorware Macintosh	Authorware
APP	Add-in application file	Symphony
APP	Application object file	dBASE Application Generator
APP	Application	FoxPro
APP	Application and Application Bundle	Mac OS X
APP	Executable workflow / macro file	Automator
APP	Executable application file	DR-DOS - NeXTstep - Atari
APP	Generated application	FoxPro
APR	Employee performance review	Employee Appraiser
APW	Authorware Windows	Authorware
APX	Appexpert database file	Borland C++ 4.5
AQF	Analyzer Queries and Filters	Actix
AR	Argon - for 3D Modeling	Ashlar-Vellum
AR7	Archive	AR7
ARC	Archive	ARC - PKARC/PKXARC - PKPAS - PKUNPAK - QUARK
ARC	Archive	SQUASH
ARC	Nintendo proprietary archive format	Various Nintendo games
ARD	Map	Holux - Alan
ARF	Automatic Response File
ARH	Archivers definitions file	DN
ARI	Archive	ARI
ARJ	Archive	ARJ - ARJZ
ARK	ARC archive	CP/M port of ARC file archiver
ARK	Archive	QUARK
ARK	Managing your Money Archive File
ARR	Arrangement	Atari Cubase
ART	Gerber artwork	Cadence Allegro
ART	First Publisher, Designworks, Greenstreet Draw graphic file	All GST/Greenstreet Draw products
ART	Graphics (scrapbook)	Art Import
ART	Graphics format (Another Ray Tracer)	PFS:1st publisher - Art Import
ARTX	file format	Artisteer
ARTX	file format	belightsoft Text Art
ARX	Archive	ARX
ASC	ASCII text file
ASC	Transport armor file	PGP
ASD	Autosave file	Microsoft Word
ASD	Presentation	Astound
ASD	Screen driver	Lotus 1-2-3
ASD	Spectral Data Set	ASD Inc. RS3 spectral acquisition program
ASE	Velvet Studio Sample	AWAVE
ASE	ASCII Scene Export	3D Studio
ASF	Datafile (APL Shared File)	STATGRAPHICS (APL*Plus/PC)
ASF	Screen font	Lotus 1-2-3
ASF	Advanced Streaming Format (Compressed Windows audio/video)	Microsoft Corporation
ASK	SYSGEN answer file	RT-11
ASH	Assembly language header file	TASM 3.0
ASI	ASIC language source	ASIC
ASI	Assembler include file	Turbo C - Borland C++
ASM	Assembler language source	TASM, MASM, NASM, Yasm, FASM
ASMX	ASP.NET Web Service	Microsoft Corporation
ASO	Assembler object (object-oriented) file	Turbo Assembler
ASP	ASPECT source code file	Procomm Plus
ASP	Association of Shareware Professionals OMBUDSMN.ASP notice
ASP	Active Server Pages of Microsoft.Net	Microsoft Corporation
ASPX	ActiveX Server Pages of Microsoft.Net	Microsoft Corporation
ASS	Amalgam Scene Specification	Halo 2 Map Editor
ASS	Advanced SubStation Alpha (Subtitles)
AST	Adobe Color Separation table for PhotoShop	PhotoShop
AST	Nintendo proprietary music streaming format	Various Nintendo games
ASV	Autosave File	MATLAB
ASW	Authorware Star	Authorware
ASX	Advanced Stream Redirector file, redirects to an ASF file (see ASF)	Microsoft Corporation
ASZ	Skin	AltDesk
AT2	Auto template	Aldus Persuasion 2.0
AT3	Atrac 3 Sound/music file	All Sony devices and programs with the Atrac 3+ specification
ATM	Adobe Type Manager data/info
ATN	Adobe Photoshop action	Adobe Photoshop
ATT	AT&T Group	GCGW
ATTF	AramOS TypeAtor Text File	AramOS TypeAtor 1.0 (Development State)
ATY	Produced when an association type is exported by 3D Topicscape	3D Topicscape
AU	Sun/NeXT/DEC Audio file	AWAVE, GoldWave
AU	Sound (audio) file	Sun Microsystems - Convert (c) Villena
AUD	Audio file	AudioRack
AUP	Audacity project file	Audacity
AUX	Auxiliary dictionary	ChiWriter
AUX	Auxiliary references	TeX/LaTeX
AUZ	Ableton Live File	Authorization File for Ableton Live
AVA	Publication	Avagio
AVB	AntiViral Toolkit Pro Bases
AVI	Audio Video Interleaved animation file	Video for Windows
AVR	Audio Visual Research	AWAVE
AVS	Audio Video Software	AVS Video Editor (video editing software)
AVT	AVATAR-coding files	A3E
AW	Text file	HP AdvanceWrite
AWA	Animations Works Accelerated Movie	Animation Works
AWD	Microsoft Fax At Work Document	Microsoft Fax At Work
AWK	AWK script/program	awk, GNU Awk, mawk, nawk, MKS AWK, Awka (compiler)
AWM	Animations Works Movie (as .AVI)	Animation Works
AWS	Data (APL Workspace)	STATGRAPHICS (APL*Plus/PC)
Ax	Directshow filter file format
AXF	ARM Executable Image generated by the ARM tools
AXF	"lightweight geodatabase" [1]	ESRI ArcPad
AXM	Axmedis object	Axmedis Tools
AZD	Amazon Software Download	Amazon Software Download
AZW	DRM enabled eBook	All models of Amazon Kindle
AZW1	DRM enabled eBook with embedded fonts	All models Amazon Kindle
AZW2	Program file	All models of Amazon Kindle excluding Kindle 1
AZZ	Data file	AZZ Cardfile

B

Ext.	Description	Used by
B&W	Black and white graphics file	atari - mac
B&W	Mono binary screen image	1st Reader
B	Batch list	APPLAUSE
B	Grand Theft Auto saved game	Any of the 3D Grand Theft Auto games in either III or IV era.
B_W	Black and white graphics file	Atari - mac
B1N	Both mono and color binary screen image	1st Reader
B30	Printer font (JLaser - Cordata)	Corel Ventura Publisher
B3D	Blitz3D files
B8	Raw graphics file (one byte per pixel) plane two	PicLab
BA	Binary Archive	Scifer Archiver and Compression [External Header Mode]
BAC	Compiled BASIC	RT-11 BASIC-11
BAD	Bad file	Oracle Corporation - many
BAD	Animation file	Novalogic
BAD	File which covers bad blocks on disk volume (not to be moved)	RT-11
BAK	Backup file
BAL	Music score	Ballade
BALANCE	Balance accounting sheet file	Balance
BAP	Blaze Audio Wave Information File	BlazeAudio MadCap Software
BAR	Horizontal bar menu object file	dBASE Application Generator
BAR	Info Bar for GFX2EXE	GFX2EXE
BAR	Broker Archive. Compressed file containing number of other files for deployment.	IBM WebSphere Message Broker
BAS	BASIC language source	QuickBASIC - GW-BASIC - FreeBASIC
BAT	Batch file	MS-DOS, RT-11
BB	Database backup	Papyrus Design Group
BBL	Bibliographic reference file	TeX/BibTeX
BBM	Brush	Deluxe Paint
BBP	Playlist	BassBox
BBQ	BitBeamer Transfer Queue file	BitBeamer
BBS	Bulletin Board System announce or text info file
BBS	Hudson-style messagebase	FTN software
BC!	Unfinished download	Unfinished BitComet download (a BitTorrent client)
BCF	Card data	Bingo Card Creator
BCH	Batch process object file	dBASE Application Generator
BCH	Datafile	Datalex EntryPoint 90
BCO	Outline font description	Bitstream Inc.
BCP	Borland C++ makefile
BCT	Backup dictionary	Clarion
BCW	Environment settings	Borland C++ 4.5
BDB	Bookends database	Bookends
BDC	Dictionary	Lingvo
BDEF	Builder Definition	Websphere Portlet Factory
BDF	Adobe Glyph Bitmap Distribution Format	Adobe Software
BDF	Binary update file	BUPDATE.EXE (c) TNT Techn.
BDF	Bitmap Distribution Format font file	X11
BDF	Datafile	Egret
BDM	Videoclip	AVCHD
BDMV	Blu-ray Video Data Content file	Media players / software that supports Blu-ray structure
BDR	Border	Microsoft Publisher
BDT	Dictionary	Lingvo
BEF	Bleck Encrypted File
BEZ	Outline font description	Bitstream
BF	Brainfuck sourcefile
BF2	Bradford 2 font
BFC	Briefcase Win95	Win95
BFM	Font metrics	unix/Frame
BFS	Binary File Storage
BFX	Fax	BitFax
BGA	Bitmap graphics
BGI	Borland Graphics Interface device driver	Turbo C - Turbo Pascal
BH	Blackhole	data compression format
BI	BASIC include file	Visual Basic - FreeBASIC
BIB	Bibliography (ASCII)
BIB	Database - not compatible with TeX format	Papyrus
BIB	Literature database	TeX/BibTeX
BIF	Binary Image Format b&w graphics file	Image Capture board
BIK	Bink video file (RAD Video)
BIN	Binary file, usually zero-start (.com analog)
BIN	SGI Powerflip
BIN	Text mode memory dump	The Draw - TUD - ACiDDraw - etc.
BIO	BioniX Wallpaper playlist file	BioniX Wallpaper Changer
BIO	OS/2 BIOS
BIT	Bitmap X11
BK!	Document backup	WordPerfect for Win
BK	Faxbook	JetFax
BK?	Backup file
BKC	Backup catalog	Backup4all
BKn	Timed backup file for document window n	WordPerfect for Win
BKP	Backup file	Write - TurboVidion DialogDesigner
BKW	Mirror image of font set	FontEdit
BLD	BLoaDable picture	BASIC
BLD	SYSGEN Build procedure file	RT-11
BLEND	Blender3D Project File	Blender
BLG	Backup Log	ARCSOLO
BLK	Temporary file	WordPerfect for Win
BLOB	Unknown	Steam (software) for Win
BLP	Blizzard Game Picture	Blizzard Entertainment games (various)
BM	BitMap graphics file
BM3	UIQ3 Phone backup
BMD	Nintendo proprietary 3D model file	Various Nintendo games
BMK	Help Bookmarks	Windows 3.x
BMP	OS/2 or Win graphics format (BitMap Picture)	QPeg - CorelDraw - PC Paintbrush - many
BMPW	bitmap world-file - geo-references info
BMS	Nintendo proprietary MIDI tracker format	Various Nintendo games
BMT	Ami Pro Button	Ami Pro
BNA	Data	Atlas Boundary
BNK	Adlib instrument bank file
BNR	Graphics Banner	Banner - Poster
BOK	Shamela Library book	Shamela Library Program
BOO	Book-format	READIBM
BOO	Compressed file ASCII archive created by BOO (msbooasm.arc)	msbooasm.arc
BOO	Boo programming language source file	Boo Programming Language
BOT	Bot files, these go with JKB files	Quake 3 Engine
BPC	Chart	Business Plan Toolkit
BPOLY	Data	Prisms binary 3D object
BPP	Backup application	Clarion
BPT	Bitmap fills file	CorelDRAW
BPW	Bitser proprietary encrypted password file	Bitser password manager
BR	Script	Bridge
BRD	Eagle Layout File
BRD	Tanzzle board file	Tanzzle
BRD	Cadence Allegro board file	Cadence
BRF	Braille	Braille embossers and refreshable displays
BRK	Fax	Brooktrout Fax-Mail
BRK	The Brake! Mailer REXX script	The Brake!
BRL	CAD	Ballistic Research Laboratory CAD
BS	Boot sector file	SYSLINUX
BS2	Archive	BS2.EXE
BSA	Archive	BSArc
BSC	Compressed Apple II file archive created by BINSCII	BINSCII
BSC	Database	Source Browser
BSC	Pwbrmake object file	Microsoft Fortran
BSP	GoldSource/Source engine map files	Valve Corporation
BSP	id Tech map files	id Software
BSS	boot sector (DOS) file	SYSLINUX
BSS	Casio Phone base	PC-LINK
BST	BiblioTex file (BiblioTex=bibliography file)	TeX
BSY	Busy flag	FTN soft
BTM	Batch-to-memory (quick batch)	4dos -ndos
BTN	Makeover Button file
BTX	backup of 4DOS batch files (_4INST.BTM)	4DOS
BUFR	Binary Universal Form for the Representation of Meteorological Data
BUG	Bugs and Problems
BUN	LucasArts Bundle File
BUP	Backup file
BUT	Button definitions	Buttons!
BUY	Datafile format	movie
BVn	Overflow file below insert point in Doc n	WordPerfect for Win
BWB	Spreadsheet application	Visual Baler
BWR	Beware (buglist)	Kermit
BYU	BYU Movie	BYU
BZ2	Archive	bzip2
BZM	Map	Blitzkrieg

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.	Watcom C/C++, Borland C/C++, gcc and other C compilers
C	Unix file archive	COMPACT
C++	C++ language source
C00	Print file	Ventura Publisher
C01	Typhoon wave files	AWAVE
C32	COMBOOT Executable (32-bit)	SYSLINUX
C86	C source code file	Computer Innovation C86
CA	Initial cache data for root domain servers	Telnet
CA?	Borland packed and split file	Borland Installer
CAB	Win 95 packed file	Win 95
CAC	dBASE IV executable when caching on/off (see cachedb.bat)
CAD	Drawing	BobCAD-CAM
CAD	Document	Drafix Windows CAD
CAL	Calendar file	Windows 3.x
CAL	Spreadsheet format	SuperCalc
CALS	Computer Aided Acquisition and Logistics
CALS	Support Raster Format
CAM	Casio Camera
CAN	Fax	Navigator Fax
CAP	Caption	Ventura Publisher
CAP	Capture file	ProComm - Telix
CAS	C + ASM language source	Turbo C
CAT	Catalog	CP Backup - dBASE IV
CAT	Device driver digital signature	Microsoft Windows
CAT	Stellarium Star Catalogue	Stellarium
CATDrawing	Drawing file of CATIA V5	CATIA V5
CATPart	Part file of CATIA V5	CATIA V5
CATProduct	Assembly file of CATIA V5	CATIA V5
CATS	Combined source	ATS
CBA	Source code	Creative BASIC
CBC	Fuzzy logic system	CubiCalc
CBL	COBOL source code file
CBM	Compiled bitmap graphics	XLib
CBR	Comic Book Reader (RAR file)	CDisplay and similar
CBS	MasterWord button bar configuration file
CBT	COMBOOT Executable (incompatible with DOS COM files)	SYSLINUX
CBT	Computer Based Training	many
CBZ	Comic Book Reader (ZIP file)	CDisplay and similar
CC	C++ source code file
CC	CC language source	CC
CCC	Bitmap graphics (native format)	Curtain Call
CCF	Communications configuration file	Symphony
CCF	Color Chat file	Color Chat File
CCH	Chart	CorelChart
CCITT	CCITT Group 3 and Group 4 Encoding
CCL	Communication Command Language file	Intalk
CCO	BTX Graphics file	XBTX
CCT	Print Template	BobCAD-CAM
CD	CD description	DN
CDA	CD-Audio	Win95
CDB	Card database	CardScan
CDB	Main database	TCU Turbo C Utilities
CDF	Common Data Format
CDF	Company Data File	Nominal Small Business Accounting software
CDF	Computable Document Format	Mathematica
CDF	Cyberspace Description Format
CDF	Graphics	netcdf
CDK	Document	Atari Calamus
CDL	CADKey CADL Language	CADKey
CDM	Disk Drivers NPA	Novell NetWare
CDM	Music format (compressed)
CDO	Music notation	Crescendo Music Notation Editor
CDR	Vector graphics format (drawing)	CorelDraw!
CDT	Corel Draw Template File	CorelDraw!
CDX	Compound index file	Visual FoxPro, Advantage Database Server
CE	Computer Eyes	Conversion Artist
CE	Main.ce	The FarSide Computer Calendar
CEB	Cont. Edge Bitmap	Conversion Artist
CEF	CA-Clipper Workbench Application	CA Clipper
CEF	Export File
CEF	Compact Embedded Font	Adobe Illustrator
CEG	Bitmap graphics	Tempra Show - Edsun Continuous Edge Graphics
CEL	Animation CEL	3D Studio
CEL	Graphics	Autodesk Animator - Lumena
CF	Configuration file	imake
CFA	Audio file	Adobe Premiere Pro
CFC	ColdFusion Component	Adobe ColdFusion
CFG	Configuration file
CFL	Chart	CorelFLOW
CFM	ColdFusion Markup Language	Adobe ColdFusion
CFN	Font data	Atari Calamus
CFO	C Form Object internal format object file	TCU Turbo C Utilities
CFP	Fax	The Complete Fax Portable
CFT	CFast graphics file	Disney Animation Studio
CGA	CGA display font	Ventura Publisher
CGI	Common Gateway Interface script
CGM	Computer Graphics Metafile vector graphics	A&L - HG - many
CH	Clipper language header	CA Clipper
CH3	Chart	Harvard Graphics 3.0
CH4	Presentation	Charisma 4.0
CHD	Font descriptor	FontChameleon
CHI	ChiWriter Document	ChiWriter - Chiview
CHK	Recovered data	DOS CHKDSK
CHK	Temporary file	WordPerfect for Win
CHL	Configuration History Log
CHM	Compiled Help File	Microsoft Windows, Help Explorer Viewer
CHML	Encrypted Data File	Krasbit Technologies, Chameleon Imaging Workflow Software
CHN	Data	Ethnograph 3
CHP	Chapter file	Ventura Publisher
CHR	Character set	Turbo C - Turbo Pascal
CHT	Chart	Harvard Graphics 2.0 - SoftCraft Presenter
CHT	CHeaT in any program/game	many
CHT	Interface file for ChartMaster	dBASE
CHZ	Archive	CHARC
CIF	Caltech Intermediate Format graphics file
CIF	Chapter information	Ventura Publisher
CIF	Crystallographic Information File	RasMol, Jmol
CiM	C Text Mode Image File	The Ultimate Draw
CIX	Database index	TCU Turbo C Utilities
CKB	Borland C++ 4.x editor keystroke mapping	BCW.EXE
CL	COMMON LISP source code file
CLA	Source	Clarion
CLASS	Java class file	Java
CLD	Clipper debugger configuration file	CA Clipper
CLJ	Clojure source code	Clojure
CLP	Clip art graphics file	Quattro Pro
CLP	Clipboard file	Windows 3.x
CLP	Compiler response file	CA Clipper
CLP	Graphics format	PCPAINT/Pictor
CLPI	ClipAV Clip Information file for Blu-ray	Media hardware / software with Blu-ray structure support
CLPRJ	ClassicLadder project file	ClassicLadder
CLR	Color binary screen image	1st Reader
CLR	Color definitions	Photostyler
CLR	Color scheme	Boxer/2
CLR	Palette file for GIS format
CLS	C++ class definition file
CLW	MFC Class Wizard information	Microsoft VC++
CM	Data file	CraftMan
CMB	Xtree for Windows Button Bar file
CMD	Command	dBASE - Waffle
CMD	Command Prompt batch file	Microsoft Windows NT based operating systems
CMD	executable programs	CP/M-86 operating system
CMD	External command menu	1st Reader
CMD	OS/2 batch/REXX file	OS/2
CMF	FM-music file (Creative Music File)
CMK	Card	Card Shop Plus
CMM	CMM script (batch) file	CEnvi
CMP	Bitmap graphics (Lead CMP compression)
CMP	Compressed data	PKWare Inc. data compression library
CMP	Header file for PostScript printer files	CorelDRAW
CMP	Photofinish Calibration Map	Photofinish
CMP	User dictionary	Microsoft Word for DOS
CMRL	Concise message routing language	DOTGO
CMS	Content Management System	Any Web Browser
CMU	Carnegie Mellon University Formats
CMV	Animation (CorelMove CorelDraw 4.0)	CorelMove CorelDraw 4.0
CNC	CNC general program data
CND	System generation conditional file	RT-11
CNF	Configuration (program - printer setup)	program - printer setup
CNF	Configuration file
CNV	Temporary file	WordPerfect for Win
CNV	Winword DLL used as part of an import operation (CNV=converter)	Microsoft Word
CO	Cobalt - parametric drafting and 3D modeling	Ashlar-Vellum
COB	Calgari trueSpace2 File Format
COB	COBOL source code file
COD	Code definition table	UUPC
COD	Datafile	Forecast Plus - Microsoft Multiplan - StatPac Gold
COD	file uncluding CODES for any program/game	many
COD	Printer code definition file	Boxer/2
COD	Program compiled code	FORTRAN
COD	Template source file	dBASE Application Generator
COD	Videotext file
COE	Coefficient file	Xilinx ISE
COF	Animation Control File	Diablo II
COL	Color palette	Autodesk Animator - many
COL	Spreadsheet	Microsoft Multiplan
COM	Command (memory image of executable program)	DOS
COM	Indirect command file (sequence of commands to be executed)	RT-11
CON	Configuration file	Simdir
CON	MSTS Consist file	MSTS
CPC	Compressed image	Cartesian Perceptual Compression
CPD	Script	Complaints Desk
CPF	Fax	The Complete Fax
CPI	ColorLab Processed Image bitmapped graphics file
CPI	MS-DOS codepage file	MODE.EXE
CPL	Control panel file	Windows 3.x
CPL	Presentation	Compel
CPMZ	ConPro/Miradi Zipfile	Miradi and ConPro
CPP	C++ language source	Watcom C/C++
CPP	Presentation	CA-Cricket Presents
CPR	Knowledge Access	GCGW
CPS	backup of startup files by QEMM (?) autoexec.cps
CPT	Encrypted memo file	dBASE
CPT	Mac file archive	COMPACT PRO
CPT	Template	CA-Cricket Presents
CPZ	Music text file	COMPOZ
CR2	Raw image format	Canon digital cameras
CRA	Advanced crack file (usually text)
CRD	Cardfile	Windows 3.x - YourWay
CRD	Map	Holux - Alan
CRD	Molecular coordinates	CHARMM, RasMol
CRDOWNLOAD	Google Chrome download in progress	Google Chrome
CRF	Cross-reference	Microsoft MASM - Zortech C++, RT-11 CREF
CRK	Crack file (usually text)
CRP	Encrypted database	dBASE IV
CRS	File Conversion Resource	WordPerfect 5.1
CRT	Terminal settings information	Oracle
CRU	Compressed file archive created by CRUSH
CS	C# source file	C#
CSD	Compact Shared Document	Dream To Reality
CSG	Batch file (Submit)	ISIS/w
CSG	Graph	Statistica/w
CSM	Borland C++ 4.x precompiled header file	BCW.EXE
CSP	PC Emcee Screen Image file	Computer Support Corporation
CSS	Datafile	CSS - Stats+
CSS	Datasheet	Statistica/w
CSS	cascading style sheet
CSV	Adjusted EGA/VGA palette	CompuShow
CSV	Comma Separated Values text file format (ASCII)
CTC	Control file	PC Installer
CTF	Character code translation file	Symphony
CTK	CommonTime Key file	CommonTime software applications
CTL	Control file	dBASE IV - Aldus Setup
CTL	BATCH control file (generated by BATCH from .BAT file)	RT-11
CTT	BATCH Temporary file	RT-11
CTX	Ciphertext file	Pretty Good Privacy RSA System
CTX	Course TeXt file	some Microsoft online guides
CTX	document	Creativyst Table eXchange
CUF	C Utilities Form definition	TCU Turbo C Utilities
CUR	Windows resource (cursor image file)	Resource Workshop - WRT - Watcom Resource Editor
CUT	Graphics format (bitmapped graphics)	dr. Halo
CV4	Color file	CodeView
CVP	Cover page	WinFax
CVS	Graphics	Canvas
CVT	Backup file for CONVERTed database file	dBASE IV
CVW	Color file	CodeView
CWEB	C Web
CWK	Datafile	ClarisWorks, Appleworks
CXX	C++ source code file	Zortech C++
CYS	Cytoscape session file	Cytoscape

D

Ext.	Description	Used by
D	D Programming Language source file	DMD
D3V	Video file	Nintendo DS (with ARME, MMCF etc.)
D4D	Data	Draw 4D object
D4P	Data	Draw 4D Pro object
D64	Commodore 64 disk image
D88	Toshiba Pasopeia D88 disk image format	A series of emulators of Japanese computers
DAA	Direct Access Archive
DAE	COLLADA file
DAF	Data file	Digital Anchor
DAT	Maxum chromatograph chromatogram	Siemens Maxum Chromatograph
DAT	LDraw (Sub)Part File, 3D Model	LDraw
DAT	Document	Microsoft Word Format (old)
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
DB$	Temperature debug info	Clarion Modula-2
DB$	Temporary file	dBASE
DB	Database file	Paradox - XTreeGold - dbvista - Oracle - XoftSpySE - Windows thumbnail cache
DB	Configuration	dBASE IV - dBFast
DB	Multi Edit config	ME
DB2	Database	dBASE II
DB3	Database	dBASE III
DBA	Database file	Turbo Prolog - DataEase
DBA	DarkBasic source code
DBC	DataBaseContainer	Visual FoxPro
DBD	Business data	Business Insight
DBD	Debug info	Clarion Modula-2
DBF	Database file	dBASE III/IV - Visual FoxPro - dBFast - DataBoss - DBVista - CA-Clipper - Visual Objects - Alaska Xbase++ - Advantage Database Server
DBG	Debugger script	DOS debug - Watcom debugger
DBG	Symbolic debugging information	Microsoft C/C++
DBK	Database backup	dBASE IV
DBL	DIBOL source file
DBM	Datafile	DataEase
DBM	Menu template	DataBoss
DBO	Compiled program	dBASE IV
DBPro	DarkBasicPro Project
DBS	Data file used by Managing Your Money
DBS	Database in SQL Windows format
DBS	Datafile	PRODAS
DBS	Printer description file	Microsoft Word, Microsoft Works
DBT	FoxBASE+ style memo	FoxPro 2.x
DBT	Memo file for database w/same name	dBASE IV - dBFast
DBW	Windows file	DataBoss
DBX	DataBeam	GCGW
DBX	AutoCAD Database	AutoCAD
DBX	Archive File	Outlook Express
DC	CAD drawing file	DesignCAD 3000 for Windows
DC6	Image file	Diablo II
DCA	Document Content Architecture text file	IBM DisplayWrite
DCC	Animation	Diablo II
DCD	CAD Drawing File	DesignCAD 3DMax for Windows
DCF	floppy disk image	Disk Copy Fast
DCH	Schematic Drawing file	DipTrace Schematic Capture
DCI	Dreamcast Save File	Dreamcast
DCL	Delphi Control Library	Borland Delphi
DCM	DCM music module	AWAVE
DCP	OS/2 device code page	OS/2
DCS	Bitmap graphics (CYMK format)	QuarkXPress
DCS	Datafile	ACT! Activity Files
DCT	Dictionary: used by many programs with program dependent format	Clarion
DCT	Spell checking dictionary	Harvard Graphics 3.0 - Symphony
DCT	DataBaseContainer Extension	Visual FoxPro
DCU	Delphi unit (compiled)	Borland Delphi
DCW	Walter Machine Programing	Walter Profile Editor
DCX	Multi-page PCX graphics (common fax format)	Intel - SpectraFAX
DCX	DataBaseContainer Index	Visual FoxPro
DD	Macintosh file archive	DISKDOUBLER
DDA	Data	GLBasic ASCII 3D object
DDB	Bitmap graphics
DDB	Digidesign Database File	Digidesign Pro Tools
DDI	Disk image	DiskDupe
DDP	Device Driver Profile file	OS/2
DDS	DirectDraw Surface file	Microsoft Flight Simulator, other Microsoft programs
DEB	DEBUG script	DOS Debug
DEF	Assembly header file	Geoworks
DEF	Defaults - definitions
DEF	Linker definition file	TLink - WLink...
DEM	Demonstration
DEM	Digital Elevation Model
DEM	Graphics file	VistaPro
DEM	Vista DEM file	Meta.exe VP3
DES	Ascii text parameter description	AWAVE
DESKLINK	Windows Explorer Desktop Control (commonly "Desktop (create shortcut).DESKLINK", 0 bytes). Uses a 'special' hidden file extension (NeverShowExt flag inside the Registry), overriding the Windows Explorer option of showing/hiding file extensions.
desktop	Desktop Entry	freedesktop.org
DEV	Device driver
DEV	SYSGEN handler build procedure	RT-11
DEV	Dev-C++ project file	Dev-C++
DFD	Data Flow Diagram graphic file	Prosa
DFF	RenderWare model data (e.g. Grand Theft Auto III and later)
DFI	Outline font description	Digifont
DFL	Default program settings	Signature
DFM	Data Flow Diagram model file	Prosa
DFM	Delphi form module	Borland Delphi
DFS	Delight Sound File
DFV	Printing form (Word)	Microsoft Word
DFX	Micrografx Effects DLL
DGN	Graphics file	MicroStation
DGS	Diagnostics
DH	Dependency information for .ph	Geoworks
DHP	Dr. Halo PIC Format graphics file	Dr. Halo II - III
DHT	Datafile	Gauss
DI	D Programming Language interface file	DMD
DIA	Diagraph graphics file	Computer Support Corporation
DIB	Device Independent Bitmap	rarely used Windows 3.0 bitmap; Win - OS/2
DIC	Dictionary (e.g. from WinWord)
DIF	Borland patch data file	Borland patch
DIF	Data Interchange Format	Visicalc
DIF	OS/2 V2.2 Display Information File	OS/2
DIF	Output from Diff command - script for Patch command
DIF	SRCCOM, BINCOM output file	RT-11
DIG	Digilink	AWAVE
DIG	Sound Designer 1 audio file	AWAVE
DIP	Graphics
DIP	Watcom debug info processor	WatcomDebugger
DIP	PCB Drawing file	DipTrace PCB Layout
DIR	Dialing directory file	Procomm Plus
DIR	Directory file	VAX - CPS Backup
DIR	Movie	MacroMind Director 4.x
DIR	Directory listing file	RT-11
DIS	Distribution file	VAX Mail
DIS	Thesaurus	CorelDraw
DIZ	Description file (Description In Zip)
DJVU	DJVU Document Format, a format similar to PDF but with higher compression rates at the same quality.	DJVU
DKB	Raytraced graphics	DKBTrace
DL	Animation format (Italian origin)	Display - DL Viewer
DLD		Lotus 1-2-3
DLF	Dialogue Live Format	Produced by Exstream Dialogue and edited by Dialogue Live Editor
DLG	Dialog resource script file	Microsoft Windows SDK
DLG	Dialog resources	DN
DLG	Windows SDK dialog editor data file
DLG	Windows SDK dialog editor data file
DLL	Dynamic-link library	Windows 3.x - OS/2
DLL	Export/import filter	CorelDRAW
DLM	Microsoft File Transfer Manager	Microsoft File Transfer Manager
DLP	Data	DAQLab
DLS	Setup	Norton Disklock
DMF	Music format (Delusion Digital Music File)	Delusion
DMF	DeleD files
DMG	Apple Disk Image	Mac OS X (Disk Utility),
DMO	Demo	Derive
DMP	Dump file (e.g. screen or memory)
DMP	DUMP utility output file	RT-11
DMS	Amiga file archive	DISKMASHER
DNG	Digital Negative (DNG), 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
DNT	data	RSNetWorx Project
DO	Java servlet file	Web browser (Various)
DOC	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 2007 Master document	Microsoft Word 2007
DOCX	Office Open XML Text document	Microsoft Word
DOF	Delphi project options file	Borland Delphi
DOG	Screen file	Laughing Dog Screen Maker
DOH	Dependency information for .poh	Geoworks
DOR	Roland Digital audio file	Roland
DOS	External command file	1st Reader
DOS	Network driver (e.g. pkt_dis.dos)
DOS	OS/2 V3 SVGA PMI-File	Svga.exe
DOS	renamed system files (AUTOEXEC.BAT, COMMAND.COM, CONFIG.SYS,DBLSPACE.BIN, DRVSPACE.BIN, IO.SYS, MSDOS.SYS) of previous MS-DOS version	Windows 95, 98, ME (dual-boot feature)
DOS	Text file containing DOS specific info
DOT	Line-type definition file	CorelDRAW
DOT	Microsoft Word document template	Microsoft Word
DOTX	Office Open XML Text document template	Microsoft Word
DOX	Text file	MultiMate 4.0
DOZ	Description Out of Zip	VENDINFO
DP	Calendar file	Daily Planner
DP	Data file	DataPhile
DPR	Default project- and state-related information	Borland C++ - Delphi - C
DPF	Bareboard PCB CAD/CAM format	Ucamco
DPX	Digital Moving Picture Exchange
DRP	Web3D File	Web3D
DRS	Display Resource	WordPerfect for Win
DRV	Driver
DRW	Designer vector graphics file	Designer - MicroGraphix
DS	TWAIN Data Source	Any twain-source must supply one xxx.ds file
DS1	Map file	Diablo II
DS4	Vector graphics	Micrografx Designer 4.x
DSC	Celestia Deep Space Catalog file	Celestia
DSC	Description file
DSC	Discard file	Oracle
DSD	Database	DataShaper
DSF	Data Storage Format	Golden Helix
DSF	Delusion Digital Sound File	Delusion
DSK	Desktop configuration	BP - DN - BC++ - TP
DSK	Disk Drivers	Novell NetWare
DSK	Logical disk file	RT-11
DSM	Digital Sound Module	DSI
DSN	Design	Object System Designer
DSP	Display parameters	Signature
DSP	Dynamic Studio Professional Module	Dynamic Studio
DSP	Graphics display driver	Dr. Halo
DSP	Norton viewer DLL	Win
DSP	Visual Studio 6 project file	Microsoft Visual Studio
DSR	Driver Resource	WordPerfect for Win
DSS	Screensaver file	DCC
DSS	Digital Speech Standard (Sound)	Digital Soup
DSS	SQL Script for .Time Framework	Exaktime
DST	Tajima Embroidery Format	Embroidermodder
DST	WAIN (Scanner spec) data source DLL	Win
DSV	Nintendo DS battery save	DeSmuME, DraStic
DSW	Borland C++ 4.x desktop layout file	BCW.EXE
DSY	DAISY container file	ADAKTA.EXE
DT1	Tile file	Diablo II
DT2	msn-emoticon	paint
DT_	Data fork of a Macintosh file	Mac-ette
DTA	Data file	Turbo Pascal - PC-File - Stata
DTB	Database Backup for .Time Framework	Exaktime
DTF	Database file	PFS - Q&A
DTL	Django template language	djangoproject
DTM	DigiTrekker music module	AWAVE
DTO	data	Directory Toolkit output
DTP	Desk Top Publishing Document	Timeworks / greenstreet Publisher3/ Greenstreet Publisher 4.5
DTP	Page Magic 2.0 publication	Page Magic 2.0 upgrades to Greenstreet Publisher
DTP	Publication	Publish-It! upgrades to Greenstreet Publisher
DTS	Torque Game Engine model format
DVC	Data	Lotus 1-2-3
DVDPROJ	iDVD project file	iDVD (Apple iLife '08)
DVI	DeVice Independent document	TeX
DVP	DESQView run-file	DESQView
DVP	Device parameter file	AutoCAD
DW2	Drawing	DesignCAD for DOS, & DesignCAD for Windows
DWB	Coryphaeus Software Designers Workbench	CSD
DWC	Archive	DWC
DWD	DiamondWare Digitized file	AWAVE
DWG	Drawing	AutoCAD, IntelliCAD, PowerCAD, Drafix, etc.
DWZ	DVD MovieFactory for TOSHIBA Project File, Designer vector graphics file	Designer - MicroGraphix or TOSHIBA
DX	Text file	DEC WPS/DX format - DEC WPS Plus
DXF	Dialogue Exchange Format	Exstream Dialogue
DXF	Drawing Interchange File Format vector graphics	AutoCAD, IntelliCAD, PowerCAD, etc.
DXN	Fax	Fujitsu dexNET
DXP	SpotFire data	TIBCO Spotfire
DXP	ISO creation project file	CD Burner XP Pro
DYLIB	Dynamic Library	Mac OS-X
DYN	Data	Lotus 1-2-3

E

Ext.	Description	Used by
E	E language source code	E
E##	EnCase Evidence File chunk	EnCase Forensic Analysis Suite
E2D	2-dimensional vector graphics file	Editor included in JFire
EAS	Extended file attributes	OS/2
EAR	Enterprise archive	archive
EBA	Source code	Emergence BASIC
EBJ	Error-checking object file	Geoworks
EBQ	CITE standard electronic BQ exchange file
EC	Error checking preprosessed Goc source code	Geoworks
EC	Source code	Ecere SDK
ECC	Error-checking file	dvdisaster
ECE	Escenic Contentng Engine dynamic page	Escenic
ECMS	Status document	ECMerge
ECMT	Template document / Session	ECMerge
ED5	EDMICS	GCGW
EDA	Ensoniq ASR disk image	AWAVE
EDE	Ensoniq EPS disk image	AWAVE
EDF	European data format	Medical timeseries storage files
EDF	Exchequer Document Format	IRIS Software
EDK	Ensoniq KT disk image	AWAVE
EDL	EDL	Premiere
EDQ	Ensoniq sq1,2/ks32 disk image	AWAVE
EDS	Ensoniq SQ80 disk image	AWAVE
EDT	Default settings	VAX Edt editor
EDT	Ensoniq TS disk image	AWAVE
EDT	External editors definitions	DN
EDV	Ensoniq VFX-SD disk image	AWAVE
EEB	Button bar for Equation Editor	WordPerfect for Win
EFA	Ensoniq ASR file	AWAVE
EFA	Encrypted File Archive
EFE	Ensoniq EPS file	AWAVE
EFE	Ensoniq EPS instrument file	AWAVE
EFK	Ensoniq KT file	AWAVE
EFQ	Ensoniq SQ1/SQ2/KS32 file	AWAVE
EFS	Ensoniq SQ80 file	AWAVE
EFT	Ensoniq TS file	AWAVE
EFT	High resolution screen font	ChiWriter
EFV	Ensoniq VFX-SD file	AWAVE
EFX	Fax	Everex EFax
EGA	EGA display font	Ventura Publisher
EKA	Internal data files	Borland's Eureka
EL	ELISP source code file	Emacs lisp
ELB	Synergy/DE library
ELC	Compiled ELISP code	Emacs lisp
ELFO		ElsterFormular
ELI	Archive	ELI
ELT	Event list text file	Prosa
EMAKER	E language source code (maker)	E
EMD	ABT Extended MoDule	AWAVE
EMF	Microsoft Enhanced Metafile
EML	Stationery Template	Outlook Express
EMU	Terminal emulation data	BITCOM
ENC	Encoded file - UUENCODEd file	Lotus 1-2-3 - uuexe515.exe
ENC	Music	Encore
END	Arrow-head definition file	CorelDRAW
ENFF	Extended Neutral File Format
ENG	Dictionary engine	Sprint
ENG	English documentation
ENG	Graphics file (charting)	EnerGraphics
ENV	Envelope or Environments
ENV	Enveloper macro	WOPR
ENV	Environment file	WordPerfect for Win
EOT	Embedded Open-Type
EPA	Award BIOS splash screen	Award BIOS, XnView
EPD	Publication	Express Publisher
EPI	Document	Express Publisher
EPI	Encapsulated PostScript graphic file
EPS	Encapsulated PostScript (Graphics format)	CorelDraw - PhotoStyler - PMView - Adobe Illustrator - Ventua Publisher
EPUB	Electronic Publication - (e-Reader format)	Okular (Linux) - Apple iBooks - Sony Reader - Adobe Digital Editions - Calibre (LMW)
EQN	Equation filE	WordPerfect for Win
ERD	Entity Relationship Diagram graphic file	Prosa
ERL	Erlang source code file
ERM	Entity Relationship Diagram model file	Prosa
ERR	Compiler/linker error report
ESH	Extended Shell batch file
ETH	Document	Ethnograph 3
ETF	Encrypted Text File. Used in some security programs.
ETW	Proprietary format from EnterTech for the MagicSing/Mic Karaoke product line.	Enter-Tech
ETX	Structure-enhanced text for some ascii text browsers
EUI	Ensoniq EPS family CD image	AWAVE
EVT	Events descriptions
EVY	Document	WordPerfect Envoy
EWD	Document	Express Publisher for Windows
EX3	Device driveR	Harvard Graphics 3.0
EXC	Exclude file for Optimize (do not process) (QEMM)	QEMM
EXC	REXX source code file	VM/CMS
EXE	Directly executable program	DOS
EXF	Excute file	OnHand PC
EXM	MSDOS executable, system-manager compliant (HP calculator)	HP calculator
EXP	Drawing File format	Drawing Express
EXP	Melco Embroidery Format	Embroidermodder
EXP	Protected mode EXE by PharLap Software	PharLap
EXP	Exports Library File	VisualStudio
EXT	Extensions descriptions file
EXX	Intermediate file by MsgPut	IBM LinkWay
EZW	easyOFFER document file	easyOFFER by Reagency Systems Corp.
EZF	Fax	Calculus EZ-Fax

F-L

Main article: Alphabetical list of file formats (F-L)

M-R

Main article: Alphabetical list of file formats (M-R)

S-Z

Main article: Alphabetical list of file formats (S-Z)