file extension Windows/OS2/Apple/Unix/Dos

File ExtensionsWindows/OS2/Apple/UNIX

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Universal dump utility for non-destructive dump/list/string search etc

U = Bitmap image : subsampled raw YUV file
U08 = wisosparbuch2008file open with: "%ProgramFiles%\WISO\Sparbuch 2008\wiso2008.exe" "%1"
U09 = wisosparbuch2009file open with: "%Applications%\WisoSpar2009\wiso2009.exe" "%1"
U4A = UnInstaller archive
U8 = Sample
U96 = EasyZip Temporary File
U98 = USA 98: Streets & Dest. Tour
UAP = WAP applications "User Agent Profile"
UAX = Unreal Audio File
UB = Music file (uchar)
UBB = Basic Ubas file
UBD = Basic Ubas file
UBI = Animation UBISOFT
UBM = Iphoto Mtwain Install file
UBS = Tracesrv etc Bugslayer util file
UC0 = Archive UC
UC2 = UltraCompressor II compressed archive
UCD = Prosa/ OM Use Case Diagram
UCM = Urban Chaos Game File
UCN = UltraCompressor II compressed archive
UCR = pixel image file
UD = Aol40 file
UDB = Msworks file
UDC = Fh5 Usenglsh file
UDF = Photostyler filter
UDF = Windows NT Uniqueness Database File
UDI = Corel Graphics10 Draw Skripts textures Bitmap file
UDL = MS Data Link
UDO = 3d Graphic
udog = (MAC FILE_TYPE) Apple Browser Launcher
UDP = User Datagram Protocol
UDT = UDTDemo.Document open with: UDTDEMO.EXE /dde
UDW = Raw Unsigned DoubleWord (32-bit) Data
UE2 = UltraCompressor II encrypted file archive
UFA = UFA compressed file archive
UFDL = Mime: application/vnd.ufdl
UFO = Ulead File for Objects (Ulead PhotoImpact)
UG = AutoCAD and others : Drawing file
ugbt = (MAC FILE_TYPE) Users & Groups
UHS = Universal Hint System (binary file)
UI = Espire language source (Geoworks UI Compiler)
UI = User Interface (Sprint)
UID = "IBM Voice Type" Users file
UIF = WordPerfect for Win long prompts for Windows
UIH = Espire header file (Geoworks UI Compiler)
UIL = Bitmap image (X-Motif UIL icon file)
UIL = Mime: text/x-uil
UIN = ICQ (a variety of instant messaging) user
UIS = WindowBlinds Skin
UK = TAGCASE0 html folder file
UK_ = Mcguiness file
UKA = Fifa World Cup game data fe art Legalscr file
UKS = Msworks file
UL = Ulaw music file
ULAW = (MAC FILE_TYPE) AU Soundyer Plug-in Filau
ULAW = sound file
ULD = Procomm Plus uploaded file information
ULS = Internet; User Location Service (Internet New Media Phone)
ULT = Ultratracker music module (MOD) file
UMB = Backup by MemMaker
UMOD = Unreal Self-extracting MOD File
UMX = Unreal Game Data File
UN_ = Ntgraph Setup30 file
UND = A86 UNDefined symbols
UNI = Forecast Pro datafile
UNI = Mime: text/uri-list
UNI = Music (UniMOD/MikMOD)
UNIC = Unic Tracker v1/v2 formats (music/sound)(Asle / ReDoX)
UNIS = Mime: text/uri-list
UNIX = Unix file
UNIXYZ = UniChem chemical modeller output file
UNIXYZ = UniChem XYZ chemical modeller input file
UNPA* = glslang unpack program(* means only .unpa is tested)
UNQ = ACT! 3.0 Email message attachment
UNR = Unreal Game Data File
UNT = Unit
UNUSED = Photoline4 Defaults file
UNV = Mime: application/i-deas
UNX = Text file containing UNIX specific info
UOL = PhotoImpact Clipart Images
UP2 = Cool3d plugins board file
UPC = Ultimate Paint component
UPD = UPDate info
UPF = Bitmap image (Universal Picture Format)
UPG = Grafik Anim file
UPI = Iphoto4 Programs Plugin file
UPJ = ULead Project File
UPL = Starmoney Agent Download file
UPO = dBASE compiled update data
UPR = Claris user dictionary
UPS = Msworks file
UPX = ULead Photo Express Saved Image File
UPZ = Starmoney Agent Download file
URF = "Radar ViewPoint" universal radar format
URI = List of Uniform Resource Identifiers (WWW)
URI = Mime: text/uri-list
URIS = List of Uniform Resource Identifiers (WWW)
URIS = Mime: text/uri-list
URL = Internet Shortcut
URL = Universal Resource Locator/internet
URL_ = (MAC FILE_TYPE) Web Site Address-in Fiurl
URLS = Mime: application/x-url-list
URLS = Universal Resource Locator : List of Internet shortcuts
URT = Bitmap image (Utah Run-Length Encoded image file)
US? = MS Word for DOS/WordPerfect Font
USA = Microsoft Office Headers file
USAGE = Snort file
USB = Syssoft Sandra file
USE = gen. Log
USE = MKS Source Integrity file
USERPROFILE = Symantec Shared file
USL = LaserJet Landscape Font
USM = Audio: Unsigned Sample Module data Farandole
USP = PageMaker printer font with US Ascii extended character set
USR = User database (Procomm Plus/Turbo C++ tour)
USRP = UTM/Universe Polar Stereographic (UPS) (USRP/ASRP 1.1/1.2),(French Defense Mapping Agency)
USTAR = Mime: application/x-ustar
USTAR = Mime: multipart/x-ustar
USTAR = POSIX tar compressed archive
utbl = (MAC FILE_TYPE) Text Encoding
UTE = Rukus 110 file
UTF = AOL Updating Files (in "Tools on Demand" folder)
UTI = Spybot Includes file
UTL = QuickBooks data
UTP = BinPatch Patch Data File
UTS = Spybot Includes file
UTX = Unreal Texture File
utxt = (MAC FILE_TYPE) Unicode Text File
UU = Encoded file archive (ascii) (uudecode/uuencode)
UU = Mime: application/octet-stream
UU = Mime: application/uue
UU = Mime: text/x-uuencode
UUD = Encoded file archive (ascii) (uuencode)
UUE = Mime: application/uue
UUE = Mime: text/x-uuencode
UUE = UUEncoded file.Ascci encoded file for binary attachments
UVR = Ulead Cool 360 Viewer File
UVV = Listlabl file
UW = unsigned word Music file
UWF = UltraTracker WaveSample music file
UWL = WordPerfect User Word List
UX = Unix file
UXDC = UXDCFILE special configuration file for application(binary format) NoOpen
UYVY = Imagemagick-5.3.2 Perlmagick file
UYVY = YUV 16Bits image format

Search: Use ctrl-F to search for item

Universal dump-utility for non-destructive dump/list/search string etc

Select Extension by starting letter:

A- B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U -

V- W - X - Y - Z - OTHER - Allowed chars in Filenames - what is an extension?


If you find an extension missing, write! No guarantee given for completeness or correctness. If you feel an extension is outdated, write!
Authors and retailers: it is in the interest of us all and our customers to avoid the double use of extensions! Please help us keep this compilation up todate!
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Any questions for not listed extensions or "what program opens xxx":
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Compilation Copyright (c) 2002 R.Bitsch, Compilation Copyright (c) 2009,2010 R.Cooper-Bitsch