Alphabetically: A
Extension File Description File Type
.a
Static Library
Developer
.a00
ALZip Second Split Archive File
Compressed
.a01
ALZip Third Split Archive File
Compressed
.a02
ALZip Fourth Split Archive File
Compressed
.a2m
AdLib Tracker 2 File
Audio
.a2w
Alice World
Developer
.a3l
Authorware 3 Library
Data
.a3m
Authorware 3 Macintosh File
Data
.a3w
Authorware 3 Windows File
Data
.a4l
Authorware 4 Library
Data
.a4m
Authorware 4 Macintosh File
Data
.a4w
Authorware 4 Windows File
Data
.a5l
Authorware 5 Library
Data
.a5w
Authorware 5 Windows File
Data
.a65
Authorware 6.5 File
Data
.a6p
Authorware 6 Program
Executable
.aa
Audible Audio Book File
Audio
.aa3
ATRAC Audio File
Audio
.aac
Advanced Audio Coding File
Audio
.aaf
Advanced Authoring Format File
Video
.aam
Authorware Map File
Data
.aao
America's Army Map File
Game
.aawdef
Ad-Aware Definitions File
Misc
.aax
Audible Enhanced Audiobook File
Audio
.ab
Applix Builder File
Developer
.ab1
DNA Electropherogram File
Data
.ab2
Print Shop Address Book File
Data
.ab3
PhotoImpact 3 Album File
Data
.aba
Palm Address Book Archive
Backup
.abbu
Address Book Backup
Backup
.abc
ABC Music Notation
Audio
.abcd
AudioVisual Book Data File
Data
.abdata
Adobe Bridge Data File
Data
.abf
Adobe Binary Screen Font File
Font
.abi
DNA Chromatogram File
Data
.abk
Automatic Backup File
Backup
.abkprj
Ashampoo Backup Project
Data
.abm
Photo Album
Raster Image
.abp
AVS Barcode Profile
Data
.abr
Adobe Photoshop Brushes File
Misc
.abw
AbiWord Document
Text
.aby
AOL Address Book File
Data
.ac
Autoconf Script
Executable
.ac$
AutoCAD Temporary File
Misc
.ac3
Audio Codec 3 File
Audio
.ac5
ArtCut 5 Document
Vector Image
.ac6
ArtCut 6 Document
Vector Image
.aca
Agent Character Animation File
Data
.acb
Adobe Photoshop Color Book File
Settings
.acbl
Adobe Color Book Legacy File
Settings
.acc
Graphics Accounts Data File
Data
.accdb
Access 2007 Database File
Database
.accdt
Microsoft Access Database Template
Database
.accdw
Microsoft Access Database Link File
Database
.acd
ACID Project File
Audio
.acd-bak
Sony ACID Project Backup File
Audio
.acd-zip
Sony ACID Project With Embedded Media File
Audio
.ace
WinAce Compressed File
Compressed
.acf
Adobe Photoshop Custom Filter File
Settings
.acfm
Adobe Composite Font Metrics File
Font
.acg
Agent Preview File
Data
.acl
AutoCorrect List File
Misc
.acm
Interplay Audio File
Audio
.aco
Adobe Photoshop Color Swatch File
Settings
.acr
ACRobot Script
Executable
.acrobatsecuritysettings
Adobe Acrobat Security Settings File
Settings
.acrodata
Acrobat Data File
Settings
.acroplugin
Adobe Acrobat Plug-in
Plugin
.acs
Agent Character File
Misc
.acsm
Adobe Content Server Message File
Misc
.act
ADPCM Compressed Audio File
Audio
.action
Automator Action
Executable
.actm
AutoCAD Action Macro File
Executable
.actx
DS Game Maker Action Description File
Developer
.acv
Photoshop Curves File
Settings
.acx
Atari ST Program
Game
.ad
After Dark Screensaver
Misc
.ada
Ada Source Code
Developer
.adb
Ada Body File
Developer
.adc
Scanstudio 16 Color Image
Raster Image
.add
Dynamics AX Developer Documentation File
Misc
.addin
Visual Studio Add-in Definition File
Developer
.ade
Access Project Extension
Data
.adf
Amiga Disk File
Disk Image
.adg
Ableton Device Group
Audio
.adi
Active@ Disk Image Backup File
Backup
.adm
Administrative Template File
System
.adml
Group Policy Language-Specific Administrative Template
System
.admx
Group Policy Administrative Template File
System
.ado
Adobe Photoshop Duotone Options File
Settings
.adp
Access Project
Data
.adr
Opera Bookmarks File
Web
.ads
Ada Specification File
Developer
.adt
ACT! Document Template
Data
.adx
Approach Index File
Data
.adz
Compressed Amiga Disk File
Disk Image
.aea
AdWords Editor Archive
Backup
.aep
After Effects Project
Video
.aepx
After Effects XML Project
Video
.aet
After Effects Project Template
Video
.aetx
After Effects XML Project Template
Video
.aex
Alpha Five Compiled Global Functions File
Web
.afc
Mass Effect 2 Audio File
Audio
.afd
Alphacam Flame Drawing
CAD
.afm
Adobe Font Metrics File
Font
.afp
FileProtector Encrypted File
Encoded
.afploc
Apple Filing Protocol Location
Misc
.afs
STAAD.foundation Project File
CAD
.aft
Ancestry.com Family Tree Database
Data
.afx
Auto FX Photo/Graphic Edges Image
Raster Image
.agd
AgileGraph Data File
Data
.age3scn
Age of Empires 3 Scenario File
Game
.aggr
Adobe Captivate Aggregate File
Data
.agi
Asterisk Gateway Interface File
Developer
.agif
Active GIF Creator Project
Raster Image
.agm
DTS Multi-channel Pro Packer File
Audio
.agp
ArtGem Project File
Raster Image
.ahd
Dynamics AX Online Help Data File
Misc
.ahi
Dynamics AX Online Help Index File
Misc
.ahk
AutoHotkey Script
Executable
.ahl
eMule Metadata File
Settings
.ahs
Adobe Halftone Screen File
Settings
.ahu
Adobe Photoshop HSL File
Settings
.ahx
WinAHX Tracker Module
Audio
.ai
Adobe Illustrator File
Vector Image
.aia
Adobe Illustrator Action File
Settings
.aic
Advanced Image Coding File
Raster Image
.aif
Audio Interchange File Format
Audio
.aifb
AIF Builder Project File
Data
.aifc
Compressed Audio Interchange File
Audio
.aiff
Audio Interchange File Format
Audio
.aim
AOL Instant Messenger Launch File
Misc
.ain
AIN Compressed File Archive
Compressed
.aip
Illustrator Plug-in
Plugin
.air
Adobe AIR Installation Package
Executable
.ais
ACDSee Image Sequence File
Raster Image
.ait
Adobe Illustrator Template
Settings
.ajp
CCTV Video File
Video
.akp
Akai Sampler File
Audio
.al
A-Law Compressed Sound Format
Audio
.alaw
A-Law Compressed Sound Format
Audio
.alb
Alpha Five Library
Developer
.albm
HP Photo Printing Software Album File
Raster Image
.alc
Dynamics AX Label Description File
Data
.ald
Dynamics AX Application Label Data File
Data
.alf
ACT! Lookup File
Database
.ali
Dynamics AX Label Index File
Data
.all
Cubasis Project File
Audio
.alr
ADRIFT Language Resource File
Game
.alt
Dynamics AX Temporary File
Misc
.alv
Adobe Photoshop Levels File
Settings
.alx
ActiveX Layout Control File
Web
.alz
ALZip Archive
Compressed
.am1
Adventure Maker
Game
.am4
AutoPlay Media Studio 4 Project File
Developer
.am5
AutoPlay Media Studio 5 Project File
Developer
.am6
AutoPlay Media Studio 6 Project
Developer
.am7
AutoPlay Media Studio 7 Project
Developer
.amb
AIMMS Model File
Data
.amf
Advanced Module File
Audio
.amfm
Adobe Multiple Font Metrics File
Font
.aml
Microsoft Assistance Markup Language File
Misc
.amp
Adobe Photoshop Curves Map File
Settings
.amr
Adaptive Multi-Rate Codec File
Audio
.ams
Adobe Monitor Setup file
Settings
.amsorm
OnLine Ringman Auction Client File
Data
.amu
PictureGear Studio Photo Album File
Data
.amv
Anime Music Video File
Video
.amx
Adobe Motion Exchange File
Video
.amxx
AMX Mod X Plugin File
Plugin
.amz
Amazon MP3 Downloader File
Music
.an1
Street Atlas USA Draw File
Data
.an2
Croc Legend of the Gobbos Animation File
Game
.an8
Anim8or File
3D Image
.ani
Windows Animated Cursor
System
.anm
3D Animation File
3D Image
.anme
Anime Studio Project
Data
.ann
Help Annotations
System
.annot
Adobe Digital Editions Annotations File
Misc
.ans
ANSI Text File
Text
.any
AnyRail Layout Plan
CAD
.aob
DVD-Audio Audio Object File
Audio
.aod
Dynamics AX Object Data File
Misc
.aoi
Dynamics AX Application Object Index File
Misc
.aol
America Online File
Misc
.aos
ARCHOS PCtablet Firmware File
System
.ap
Active Page
Web
.apa
RSView Development Project Archive
Developer
.apd
ACDSee Photo Document
Raster Image
.ape
Monkey's Audio Lossless Audio File
Audio
.apf
Adobe Profile File
Misc
.api
Acrobat Plug-in
Plugin
.apk
Android Package File
Executable
.apl
ACDSee Plugin File
Plugin
.apm
Aldus Placeable Metafile Image
Raster Image
.apng
Animated Portable Network Graphic
Raster Image
.app
Mac OS X Application
Executable
.applescript
AppleScript File
Executable
.application
ClickOnce Deployment Manifest File
Settings
.appref-ms
Microsoft Application Reference File
Settings
.apr
ArcView Project File
GIS
.apz
Autoplay Media Studio Exported Project
Compressed
.ar
Unix Static Library
Compressed
.arc
Symbian OS Backup File
Backup
.arch00
F.E.A.R. Game Archive
Game
.ard
ArtiosCAD Workspace File
CAD
.arena
Quake 3 Engine Arena File
Game
.arf
WebEx Advanced Recording File
Video
.arg
AutoCAD Profile
Settings
.arh
ProTool Compressed Project File
Compressed
.ari
ARI Compressed File Archive
Compressed
.arj
ARJ Compressed File Archive
Compressed
.ark
PowerDesk Pro Archive
Compressed
.arl
AOL Organizer File
Settings
.aro
SteelArrow Web Application File
Web
.arp
Advanced RAR Password Recovery Setup
Settings
.arr
Advanced RAR Password Recovery Project
Misc
.art
AOL Compressed Image File
Raster Image
.artproj
Artifacts Project
Developer
.artwork
ArtStudio Image
Raster Image
.arw
Sony Digital Camera Image
Raster Image
.arx
AutoCAD Runtime Extension File
Plugin
.as
ActionScript File
Developer
.as4
askSam Backup File
Backup
.asa
ASP Configuration File
Web
.asat
Assemble SAT 3D Model File
3D Image
.asax
ASP.NET Server Application File
Web
.asb
Alphacam Stone VB Macro File
Executable
.asc
ActionScript Communication File
Developer
.ascii
ASCII Text File
Text
.ascx
ASP.NET User Control File
Web
.asd
Word AutoSave File
Backup
.ase
Adobe Swatch Exchange File
Settings
.asf
Advanced Systems Format File
Video
.ashbak
Ashampoo Backup Archive
Backup
.ashdisc
Ashampoo Burning Studio Image
Disk Image
.ashprj
Ashampoo Burning Studio Project
Data
.ashx
ASP.NET Web Handler File
Web
.asi
Alpha Five Variable File
Developer
.ask
askSam Database
Database
.asl
Photoshop Style
Settings
.asm
Assembly Language Source Code File
Developer
.asmx
ASP.NET Web Service File
Web
.asnd
Adobe Sound Document
Data
.asp
Active Server Page
Web
.aspx
Active Server Page Extended File
Web
.asr
ActionScript Remote Document
Web
.ass
Aegisub Advanced Substation Alpha File
Misc
.ast
Adobe Color Separations Table
Settings
.asv
Adobe Photoshop Selective Color File
Settings
.asw
ACDSee Slideshow Wizard File
Raster Image
.aswcs
Avast! Compressed Skin File
Settings
.asws
Avast! Skin File
Settings
.asx
Microsoft ASF Redirector File
Video
.at3
ATRAC3 Audio File
Audio
.at5
Lowrance Map File
GIS
.atc
AutoCAD Tool Catalog File
Settings
.ate
Office Accounting Compressed Backup File
Backup
.atf
Photoshop Transfer Function File
Settings
.ati
Office Accounting Updated Company File
Backup
.atm
Vue Atmospheres File
3D Image
.atn
Photoshop Actions File
Settings
.atom
Atom Syndication Format
Web
.atr
Atari Disk Image
Disk Image
.atrac
Sony ATRAC Audio File
Audio
.att
Web Form Post Data File
Web
.atx
Animation Master Plugin File
Plugin
.aty
Association Type Placeholder
Text
.atz
Atomic Time Zone File
Misc
.au
Audio File
Audio
.au3
AutoIt v3 Script
Developer
.aud
Video Game Compressed Audio File
Audio
.aup
Audacity Project File
Audio
.aut
AutoIt Script File
Developer
.aux
LaTeX Auxiliary File
Settings
.avastlic
Avast! License File
Misc
.avatar
Google Talk Avatar File
Raster Image
.avb
Avid Bin File
Video
.avc
Kaspersky Virus Database
Data
.avd
Movie Edit Pro Video Information File
Video
.avenirproj
StoryMill Project
Data
.avi
Audio Video Interleave File
Video
.avl
ArcView Legend File
GIS
.avr
Audio Visual Research File
Audio
.avs
AviSynth Script File
Video
.avx
ArcView Extension File
Plugin
.aw
Answer Wizard File
Data
.awb
AMR-WB Audio File
Audio
.awc
Emulex AWC Firmware Update File
Misc
.awd
Microsoft Fax Document
Raster Image
.awdb
Access Walker Database File
Data
.awg
Activeworlds Object Group File
Data
.awk
AWK Script
Executable
.awkw
Awkwords Word Generator File
Misc
.awm
AllWebMenus Project File
Web
.aws
AutoCAD Work Space File
Settings
.awt
AbiWord Template
Text
.ax
DirectShow Filter
Plugin
.axd
ASP.NET Web Handler File
Web
.axm
AXMEDIS Object
Video
.axp
CDBurnerXP Audio Compilation File
Settings
.axt
Adobe Photoshop Extract File
Settings
.axx
AxCrypt Encrypted File
Compressed
.ay
AY Chiptune File
Audio
.azw
Amazon Kindle eBook File
Data
.azw1
Amazon Topaz eBook
Data
.azz
AZZ Cardfile Database File
Data