| .b | IBM Lotus Applause Batch List Format |
| .b!k | Microsoft Flight Simulator Scenery |
| .b&w | Bitmap Image |
| .b00 | Blindwrite |
| .b01 | BlindWrite Image |
| .b02 | BlindWrite Image |
| .b1 | B1 Compressed Archive |
| .b16 | PCO Image |
| .b2 | Progress Database |
| .b24 | Ovation Pro For RISC OS C Script |
| .b25 | Ovation Pro For RISC OS DDL |
| .b26 | Ovation Pro For RISC OS Style Sheet |
| .b27 | Ovation Pro For RISC OS Document |
| .b2a | Binary To ASCII (BTOA) Encoded Format |
| .b2d | Brutus2D Source Code |
| .b2f | RISC OS Windows Metafile |
| .b30 | Ventura Publisher Printer Font |
| .b3d | BodyPaint 3D Format |
| .b3p | Native Instruments Battery Preset |
| .b4s | Winamp 3 Playlist Format |
| .b4u | Visual ReadMe |
| .b5 | MDBG Chinese-English Dictionary |
| .b5i | BlindWrite Image Format |
| .b5l | BlindWrite Image |
| .b5t | BlindWrite Image Format |
| .b60 | RISC OS PNG Bitmap Image |
| .b64 | ASCIIi Base64 MIME Encoded Archive Format |
| .b6i | BlindWrite Image Format |
| .b6l | Blindwrite License |
| .b6t | BlindWrite Table Of Contents Format |
| .ba | Scifer Archive External Archive Format |
| .ba1 | Microsoft Windows Media Center Report Log |
| .babl | DeBabelizer |
| .bac | Backup Plus Backup Format |
| .back | RMCProfile Coefficient |
| .backup | Backup Of Current ISAPI Application |
| .backupdb | Apple Time Machine Backup Folder Format |
| .bad | Microsoft Exchange Badmail Format |
| .badongo | Badongo Information Service |
| .baf | Battlefield 2 Animation |
| .bafl | BurnAware Free Compilation Format |
| .bag | PMMail Mail Index |
| .bai | BUILD2WIN Add-in |
| .bak | Backup Plus Backup Format |
| .bak2 | Microsoft FrontPage |
| .bak3 | Crysis Backup |
| .bak~ | AbiWord Auto-saved Document Format |
| .bal | Borland Programming Language Source Code |
| .bam | Bobs Adlib Music |
| .bamboopaper | Bamboo Document |
| .bamp | Easy Button & Menu Maker Project |
| .ban | MegaHAL Non-keyword List |
| .band | GarageBand Music Project Format |
| .bap | Blaze RipEditBurn Audio Wave Information Format |
| .bar | Age Of Empires / Age Of Mythology Game Format |
| .bas | Basic Source Code Format |
| .basebinary | Apple Mac OS X AirPort Base Station Binary |
| .baseconfig | AirPort Utility Setting |
| .baseproj | DNA Baser Sequence Aligner Project |
| .baserproj | DNA Baser Project Format |
| .basex | BaseX Data Format |
| .bash | Unix Shell Script (bash) |
| .bashrc | Bash Shell Startup Script Configuration Format |
| .bash_history | Bash History Format |
| .bash_login | Unix Shell Script (bash) |
| .bash_logout | Unix Shell Script (bash) |
| .bash_profile | Bash Interactive Login Shell Format |
| .basin | HEC-HMS Basin Model Settings |
| .bat | Batch File (executable) |
| .batch | Switchball Game Data |
| .bau | OpenOffice.org Configuration Format |
| .bav | AVG Bat! Plugin Format |
| .baw | BrainLED AlfaWave Session |
| .bay | Kodak/Roper Bayer Picture Sequence Format |
| .baz | Acomba Accounting Suite Backup |
| .ba_ | Renamed BAT Format |
| .bb | Blitz Basic Source Code Format |
| .bb2 | XBBS-OS/2, XGROUP, AV, ZTree Archiver Control |
| .bb3 | BlasterBall 3 Level Format |
| .bba | BlueByte Archive |
| .bbb | BlackBerry Backup (post 2012) Format |
| .bbc | BBC BASIC For Windows |
| .bbcd | BobCAD-CAM Document |
| .bbe | MindGenius Brainbloom |
| .bbf | ScriptBasic Binary |
| .bbfw | ITunes Firmware |
| .bbg | CyberSports For Basketball Game |
| .bbi | LinkOne Data |
| .bbk | TreePad Backup |
| .bbl | TeX/BibTeX Bibliographic Reference Format |
| .bblm | Mario Kart Mod Effect Format |
| .bblx | E-Sword Bible |
| .bbproject | BBEdit Project Format |
| .bbprojectd | BBEdit Project Format |
| .bbrkpuzzle | Puzzle |
| .bbrksave | Puzzle Started Status |
| .bbs | Bulletin Board System Text Format |
| .bbt | BTwin Local Database |
| .bbtl | BBEdit Tool Palette |
| .bbv | PPLive |
| .bbw | Band-in-a-Box Nterface |
| .bbx | BrainBox Neural Network |
| .bbxt | BBEdit |
| .bbz | BeBuzz Backup Format |
| .bc | Bittorrent Unfinished Download Format |
| .bc! | Bittorrent Unfinished Download Format |
| .bc5 | Impression Document |
| .bc6 | Cashflow Manager 2006 Backup |
| .bc7 | Cashflow Manager 2007 Backup |
| .bca | Allplan Backup Catalog |
| .bcb | Borland C++ Builder |
| .bcc | Borland C++ Format/makefile |
| .bcd | Microsoft Windows Boot Configuration Format |
| .bcf | Business Card Designer Pro Business Card Design Format |
| .bch | Datalex Entrypoint 90 Data |
| .bci | Belarc Advisor Computer Profile Report |
| .bck | VMX Backup Format |
| .bckp | Ad-Aware Quarantined Format |
| .bcl | Illumina CASAVA Base Call Format |
| .bcm | Business Contact Manager Format |
| .bcmx | Microsoft Outlook Business Contact Manager Customization Format |
| .bcn | Business Card Design |
| .bcp | Borland C++ Makefile |
| .bcr | Map&guide Station List |
| .bcs | Boland Calibration Settings Format |
| .bct | Adobe Bridge Cache Format |
| .bcw | Borland C++ Workspace |
| .bcx | Beam Report Standard Definition |
| .bd | BenDaglish Audio |
| .bd1 | Map Block Location |
| .bd2 | Lacerte Tax Tax |
| .bdae | Gameloft Game Data Format |
| .bdb | Microsoft Works Database Backup Format |
| .bdb2 | BrainMaster Settings |
| .bdc | Lingvo Dictionary Format |
| .bdcm | Microsoft Visual Studio BDC Model |
| .bdcr | Microsoft Visual Studio BDC Resource |
| .bdct | BBEdit Dictionary |
| .bdd | CARA Sound Radiation Data Format |
| .bde | Pro/ENGINEER Temporary |
| .bdf | Bdiff Bupdate Binary Update Format |
| .bdg | Badge Designer 2000 Photo ID |
| .bdh | Silk Performer Include |
| .bdi | Pro/ENGINEER Temporary |
| .bdic | Google Chrome Dictionary Format |
| .bdjo | Java BD-J Object Descriptor |
| .bdk | OS/2 Floppy Disk Image |
| .bdl | CoCreate Designer Bundle Format |
| .bdm | AVHCD Video Information Or Index Format |
| .bdmv | Blu-ray Information Format |
| .bdoc | DigiDoc Client Container |
| .bdof | Mario Kart Mod Effect |
| .bdp | Microsoft Exchange Diagnostic Message |
| .bdr | Microsoft Publisher Border Format |
| .bds | Cadcorp SIS Base Dataset |
| .bdsgroup | BDS Project Group |
| .bdsproj | BDS Project Format |
| .bdt | Lingvo Dictionary |
| .bdt2 | BEEDOCS Timeline 3D Timeline Document Format |
| .bdt3 | BEEDOCS Timeline 3D Timeline Document Format |
| .bdtd | Java Sun Binary DTD |
| .bdtp | BaiduPlayer Media |
| .bdv | BitDefender Vault |
| .bdw | Budget Data |
| .bdx | BitDefender |
| .bdy | DMAP Boundary |
| .bea | Beamer Song |
| .beam | Compiled Erlang Code Format |
| .bean | Bean Document Format |
| .beb | EEC Analyzer |
| .bed | UCSC BED Annotation Track Format |
| .bee | Bee Archiver Compressed Archive |
| .beh | CRiSP Calibration |
| .bejeweled2deluxesavedgame | Bejeweled 2 Deluxe Save Game Format |
| .bek | Shanda Bambook E-book |
| .bel | Belon Compressed Archive |
| .ben | SiSoftware Sandra |
| .bep | Beamer Playlist |
| .bes | MOBY Database |
| .bet | BETA Source Format |
| .bevel | FontTwister Bevel |
| .bex | BOOM Extensions To Dehacked |
| .bexpk | PGP Binary Extracted Public Key |
| .bf | Beyond Good & Evil Game Archive Format |
| .bfa | Blowfish-encrypted Format |
| .bfb | Zoo Tycoon 2 Game Model |
| .bfc | Microsoft Windows 95 Briefcase Document Format |
| .bfd | Linux BFD Rules Configuration |
| .bfe | Bcrypt - BlowFish File Encryption |
| .bff | AIX Backup Format |
| .bffm | B-17 Flying Fortress: The Mighty 8th Game |
| .bfg | Mario Kart Mod Effect Format |
| .bfi | Blaise Index |
| .bfl | Colin McRae Rally 2 Game |
| .bfli | BFLI Image Format |
| .bfm | Terminal Reality Model Format |
| .bfmv | BfMeshView Workspace |
| .bfont | Need For Speed SHIFT Font |
| .bfp | Benchmark Factory Project |
| .bfr | Network Instruments Observer |
| .bfs | SmartWare Backup Sort Definition Format |
| .bft | SmartWare Backup Transaction Definition |
| .bfw | SmartWare Backup Cross-tab |
| .bfx | Bitware BitFax Format |
| .bga | OS/2 Graphic Array |
| .bgcf | Greeting Card Design |
| .bgd | ESRI Binary Raster Definition |
| .bgeo | Houdini Binary Geometry Format |
| .bgf | ZEMAX Binary Glass Catalog |
| .bgi | BGInfo Configuration Format |
| .bgl | Microsoft Flight Simulator Scenery Data Format |
| .bgm | Basic4GL 3D Object |
| .bgo | Bigoven Recipe Card |
| .bgr | Girder Binary Plugin |
| .bgt | Graphic Accounts Account Data Format |
| .bgui | Need For Speed SHIFT GUI |
| .bgv | BonanzaGraf Financial Presentation |
| .bgw | Final Fantasy Music |
| .bgz | Blood Frontier Map Format |
| .bh | ZipTV BlakHole Archive File Format |
| .bh3 | Rise Of Nations Unit Graphic |
| .bha | Rise Of Nations Unit Graphic |
| .bhf | PcAnywhere Host |
| .bho | Behold Settings Format |
| .bhp | BHP Survey Tool Data |
| .bhs | Rise Of Nations Script |
| .bhx | BinHex Compressed File ASCII Archive |
| .bi | Microsoft Visual Basic For DOS Include |
| .bi? | LoseThos Binary Executable |
| .bib | BibTeX Document Format |
| .bibtex | BibTeX Document |
| .bic | Civilization III Game Scenario Format |
| .bid | BidMaker |
| .bidule | Plogue Bidule Sound Layout Format |
| .bie | JBIG Image |
| .bif | TomTom Navigator General Info Format |
| .bifx | Get Backup Project |
| .big | Electronic Arts Game Resource Package Format |
| .bik | BINK Video Format |
| .bikey | Bohemia Interactive Key |
| .bil | ArcView Band Interleaved By Line Image Format |
| .bim | Bytessence InstallMaker Project Format |
| .bimd | Blue Ink Meta-data Export |
| .bimx | ArchiCAD BIMx 3D Scene |
| .bin | CD/DVD Binary Image Format |
| .bin3 | LabVIEW Data |
| .bina | Microsoft Word 5 For Mac Document |
| .binarycookies | Safari Browser Cookies Package |
| .binui | Call Of Juarez Game Menu |
| .bio | OS/2 BIOS Format |
| .bioexcess | MyWinLocker Protected |
| .bionix | Bionix Wallpaper List Format |
| .biot | BiotSavart Magnetic Design |
| .bip | Character Studio Biped Format |
| .biq | Civilization 3 Scenario Format |
| .bit | Xilinx Integrated Software Environment Bitstream Format |
| .bitcfg | Passmark Configuration |
| .bitmap | X Window System Bitmap Image |
| .bitpim | BitPim Configuration Format |
| .bix | Civilization III Scenario Format |
| .biz | Print Shop Business Card Format |
| .bizdocument | Actuate BusinessReport Studio Document |
| .bjf | NTI Backup Now Related |
| .bjk | Blaise |
| .bjo | Instrument Tablature Format |
| .bk | Adobe FrameMaker Book Format |
| .bk! | Corel WordPerfect Document Backup |
| .bk0 | Aspen HYSYS Backup |
| .bk1 | Autodesk AutoCAD Backup Format |
| .bk2 | Windows Indexing Service Data Format |
| .bk3 | Corel WordPerfect Document Backup |
| .bk4 | Corel WordPerfect Document Backup |
| .bk5 | Corel WordPerfect Document Backup |
| .bk6 | Corel WordPerfect Document Backup |
| .bk7 | Corel WordPerfect Document Backup |
| .bk8 | Corel WordPerfect Document Backup |
| .bk9 | Corel WordPerfect Document Backup |
| .bkb | VariCAD Drawing |
| .bkc | Backup4all Catalog Format |
| .bkd | Book Library Local Dos Exploit |
| .bkf | Microsoft Backup Format |
| .bkg | UWXAFS Project Binary Format Data |
| .bki | IBM BookManager Backup Index |
| .bkk | BookBuddi EBook Format |
| .bkmk | Yummy FTP Bookmark Format |
| .bko | Wisco Backup Outlook Backup |
| .bkp | Backup Plus Backup Format |
| .bkr | ReplaceEm File Set |
| .bks | Microsoft Works Spreadsheet Document Backup Format |
| .bku | Timeslips Backup |
| .bkup | Backup Plus Backup Format |
| .bkw | FontEdit Image |
| .bky | Bookkey Bookmark/keyword Data |
| .bkz | FileFort Backup |
| .bla | Adobe Black Colour Separation |
| .blackhawkstriker2 | Blackhawk Striker 2 Saved Game |
| .blackhawkstriker2savedgame | Blackhawk Striker 2 Saved Game |
| .blasterball2drm3savedgame | Blasterball 2 Save Game |
| .blasterball3savedgame | Blasterball 3 Save Game Format |
| .blb | Blob Format |
| .bld | MegaPaint Picture Image Format |
| .blend | Blender 3D Data Format |
| .blend1 | Blender Backup Format |
| .blend2 | Blender Document Backup Format |
| .blf | Microsoft Windows Vista And Windows 7 Registry Format |
| .blg | Microsoft Windows Binary Performance Log Format |
| .bli | Thomson Speedtouch Series WLAN Router Firmware Format |
| .blight | Mario Kart Mod Effect |
| .blk | AutoCAD Block Template Format |
| .blkrt | Block Artist Image Format |
| .bll | Borland Delphi Localization Information |
| .blm | Eurolink Comma Separated Value |
| .bln | Golden Software Blanking File Format |
| .blob | Steam Client Registry Format |
| .blockplt | LEGO MINDSTORMS NXT Palette Format |
| .blogthis | Microsoft Windows Writer BlogThis Data Format |
| .blp | Blizzard Game Texture Format |
| .bls | Blockland Saved Game |
| .blt | AIM AOL Instant Messenger Saved Buddy List |
| .blu | FileMaker Pro Runtime Extension Format |
| .blue | EVE Online Texture |
| .bluebutton | VA Blue Button Text |
| .blv | Might And Magic 6/7 Dungeon Level Geometry |
| .blw | Adobe Photoshop Black And White Presets Format |
| .blx | Magellan MapSend Map Data |
| .bly | FIFA World Cup Game Data Fe Art Load Game |
| .blz | Nokia N-Gage Game Format |
| .bm | X Windows System Bitmap Image |
| .bm2 | Subspace/Continuum Bitmap Graphic Format |
| .bm3 | Sony Ericsson Backup Format |
| .bma | Compressed Archive |
| .bmb | Pro/ENGINEER Temporary |
| .bmc | Microsoft Terminal Server Client Bitmap Cache Format |
| .bmd | Nintendo GameCube 3D Model Format |
| .bmd5 | BookmarkingDaemon |
| .bme | Konami Beatmania Music Simulator Format |
| .bmf | Corel Gallery Binary Material Format |
| .bmg | Mario Kart Wii Message Format |
| .bmi | 3D Studio Max Plugin |
| .bmk | Bookmark Format |
| .bml | Bean Markup Language Format |
| .bmm | Tacmi Pixia Palette |
| .bmml | Balsamiq Mockups Graphic |
| .bmo | SIMATIC WinCC Script |
| .bmp | Standard Windows Bitmap Image (also OS/2) |
| .bmp24 | Bitmap Graphic |
| .bmpenx | Encrypted BMP |
| .bmq | Re-Volt Texture |
| .bms | Beatmania Music Simulator Format |
| .bmt | Alpha Five Image Library |
| .bmu | BioWare Music Unit |
| .bmw | W32/Liji-A Virus |
| .bmx | Siemens Mobile Phone Animation Format |
| .bmz | Compressed Bitmap Format |
| .bn4 | Yamaha DX100 Voice |
| .bna | Atlas Boundary Format |
| .bnc | Bojanov Encryptor Encrypted |
| .bnd | Neighbours From Hell Game Archive |
| .bndl | Bundle File Format |
| .bnf | IBM Voice Type Languages Map |
| .bng | Bingo Maker Bingo Data Template Format |
| .bnhq | BinHex Archive |
| .bni | Blizzard Battle.Net Icon |
| .bnk | Test Drive Unlimited Game Data Format |
| .bnl | MicroSim PCBoard Netlist |
| .bnp | Sony HD Camera System Format |
| .bnr | Nintento Wii Homebrew |
| .bns | Portal Script Format |
| .bnt | Entropia Universe Game Archive |
| .bny | Binary Ll Format |
| .bnz | Bingo Maker Bingo Template Or Bingo List Update Format |
| .bob | BOB Raytracer Bitmap Image |
| .bobo | ClarisWorks |
| .bobthebuildersavedgame | Bob The Builder: Can Do Zoo Save Game |
| .boc | E-Press EasyWord Big Document Format |
| .bochsrc | Bochs Configuration |
| .bod | X3 Reunion Ship |
| .boe | Microsoft Outlook Express Backup |
| .bof | IBM Voice Type Languages Tasks Enroll |
| .boh | Europa Universallis 2 Game Data |
| .bok | TestGen Test Bank Format |
| .bol | Mario Kart Course Setup |
| .bom | Apple Mac OS X Bill Of Materials Format |
| .bonds | Ribbons Bonds |
| .bonk | Bonk Audio Format |
| .boo | Microsoft Booasm.arc Encoded File Archive |
| .book | Adobe FrameMaker Book Format |
| .bookexport | Booksmart Export Format |
| .booktemplate | IBooks Author Book Template Format |
| .bookwormdeluxesavedgame | Bookworm Deluxe Saved Game |
| .boot | InstallShield Format |
| .bootefisignature | Bootefisignature Mac OS X System |
| .bootskin | Microsoft Windows Boot Skin |
| .bootstrap | Adobe HTTP Dynamic Streaming Bootstrap |
| .borland | Borland C Makefile |
| .bos | Fallout Tactics Game Archive |
| .bot | Robot Arena Game |
| .box | FoxMail E-mail Box |
| .box3d | Box Shot 3D Project |
| .boxer | Boxer For Mac Game Archive |
| .boz | Bzip Compressed Archive |
| .bp | DataFlex Business Process Object |
| .bp0 | SmartWare Backup Project |
| .bp1 | Smartware Backup Document |
| .bp2 | Autodesk AutoCAD Batch Plot Format |
| .bp3 | Autedesk AutoCAD Batch Plot Format |
| .bp4 | SmartWare Backup Project |
| .bpa | StorageSync Backup Archive Format |
| .bpb | PowerDesigner Business Process Backup Format |
| .bpc | BuildPro |
| .bpd | Pscript Binary PostScript Printer Description Format |
| .bpdx | Adobe Acrobat Catalog Batch PDX Format |
| .bpf | BatchPhoto Profile Format |
| .bpg | Delphi Project Group Format |
| .bpi | IBM Voice Type Languages New User |
| .bpj | Boxsim Simulation |
| .bpk | Nero SecurDisc Public Key Format |
| .bpkey | Blender Publisher License Key |
| .bpl | Delphi Packed Library Format |
| .bpm | Battle Planner Module Format |
| .bpmc | Bizagi Process Modeler |
| .bpmn | Avantage Template |
| .bpn | ArchiCAD Backup Format |
| .bpnueb | Payame Noor University (PNU) E-book Format |
| .bpo | DataFlex Business Process Object |
| .bpp | Clarion Backup Application |
| .bpr | Borland C++ Builder XML Project Format |
| .bps | Microsoft Works Document Backup Format |
| .bpsd | Backup Plus |
| .bpt | CorelDRAW Bitmap Master |
| .bpv | BallPark Business Valuation Valuation Scenario |
| .bpw | ArcView World File For Bip Or Bmp Images |
| .bpx | Truevision TarGA Bitmap Image |
| .bpz | Easy Blue Print Library |
| .bqf | Backdoor.Win32.Ciadoor.bqf Trojan |
| .bqw | ArcView World |
| .bqy | BrioQuery Database Format |
| .br | Omnis Data |
| .br1 | Total Commander Cached Button Bar Icons |
| .br2 | Total Commander Cached Button Bar Icons |
| .br3 | Bryce 3D Scene Format |
| .br4 | Bryce 4 Scene Format |
| .br5 | Bryce 5 Scene Format |
| .br6 | Bryce 6 Scene Format |
| .br7 | Bryce 7 Scene Format |
| .bra | Linux |
| .bragg | Bragg Profile |
| .brain | PersonalBrain Mind Map Format |
| .brasd | Mario Kart Mod |
| .brb | Bryce Object Export |
| .brc | Bryce 2 Scene |
| .brd | EAGLE Circuit Board Format |
| .bre | Breuckmann Scanner |
| .breff | Mario Kart Wii Animated Graphic |
| .breft | Mario Kart Wii Animated Graphic |
| .brep | 3D Model |
| .brew | Homebrew |
| .brf | Braille Format |
| .brfnt | Mario Kart Wii Font |
| .brg | Age Of Mythology 3D Game Model Format |
| .brh | Baraha |
| .bri | Bryce Plug-in Format |
| .bridgecache | Adobe Bridge Cache |
| .BridgeCacheT | Adobe Bridge Cache |
| .bridgelabelsandratings | Adobe Bridge |
| .BridgeSort | Adobe Bridge Cabinet |
| .bridgesupport | Bridgesupport Mac OS X File Extension |
| .brk | Brooktrout Fax Format |
| .brlcad | BRL-CAD 3D |
| .brlyt | Nintendo Wii Texture Settings Format |
| .brm | Bryce Plug-in Format |
| .brn | BrainStorm Data Format |
| .bro | Tree Professional Broadleaf Creator Format |
| .broguesave | Brogue Saved Game |
| .browser | ASP.NET Browser Definition Format |
| .brp | Tree Professional Broadleaf Creator Image |
| .brpx | E-sword Bible Reading Plan |
| .brres | Wii BRRES Resource Package |
| .brs | Adobe RoboHelp Browse Sequence Format |
| .brsar | Audio Format |
| .brstm | Audio Format |
| .brt | Booria Carpet Designer Robotuft Project |
| .brtex | Wii BRTEX Texture |
| .bru | Brutus Restore |
| .brv | BraveViewer Thumbnail Cache |
| .brw | PointCentral Financial Institutions Loan Format |
| .brx | BREW MP Application Resource Format |
| .bry2 | Bryce 2 |
| .bs | Printfox/Pagefox Image Format |
| .bs1 | VirtualBus Format |
| .bs2 | BASIC Stamp 2 Code Format |
| .bs4 | Mikogo Session Video Recording Format |
| .bs7 | Windows 7 Boot Updater Boot Animation Format |
| .bsa | Bethesda Softworks Archive Format |
| .bsave | Quickbasic BLOAD/BSAVE Format |
| .bsb | MapInfo Sea Chart Format |
| .bsc | Microsoft Visual Studio Visual C++ Source Browser Information Format |
| .bscs | Balanced Scorecard Designer |
| .bsct | Balanced Scorecard Designer Strategy |
| .bsd | BSDL Format |
| .bsdf | ZEMAX Scattering Distribution Data |
| .bsdiff | Cygwin |
| .bsdl | Boundary Scan Description Language Format |
| .bse | CRiSP Harvest |
| .bsf | AVC Blu-ray Video Format |
| .bsh | BeanShell Script Format |
| .bsi | Microsoft SharePoint Server 2007 Temporary |
| .bsk | Bryce 4 Format |
| .bsl | BSPlayer Configuration |
| .bsm | Bioshock Map |
| .bsmx | BeerSmith |
| .bsmz | Compressed BSML |
| .bsn | Autodesk TR-55 Detention Basin Storage Data |
| .bson | BSON Binary JSON |
| .bsp | Quake 2 Map Format |
| .bspr | Need For Speed SHIFT Track Map |
| .bsproj | Banned Story Project |
| .bsq | BinScii Binary Archivne |
| .bsr | Bacula Restore |
| .bss | Resident Evil Background Images Format |
| .bst | BiblioTex Format |
| .bsv | Bluespec System Verilog |
| .bsw | Business Scorecard Manager Workspace |
| .bswx | Microsoft Office PerformancePoint Server Database |
| .bsx | PBASIC Preprocessor Output |
| .bsy | VTrain Learning Cardfile |
| .bsz | BSplayer Compressed Skin |
| .bt | VTBuilder Binary Terrain Format |
| .bt! | BitSpirit Incomplete Download Format |
| .bt0 | Band-in-a-Box Temporary |
| .bt1 | Battery Analyzer Test |
| .bt2 | Batch Barcode Maker |
| .bt3 | Control Runner Button Configuration |
| .bt5 | ERP5 Business Template |
| .btapp | UTorrent Application Format |
| .btd | Business-in-a-Box Document Format |
| .btf | NationsBank Check Images |
| .btg | FlightGear Scenery |
| .bth | Bathy Recorder Data |
| .bti | Nintendo Texture Format |
| .btif | NationsBank Check Image Format |
| .btinstall | BitTorrent Installation Format |
| .btk | CLwin Tekton Database |
| .btkey | BitTorrent License Key |
| .btl | SolidWorks Sheet Metal Bend Table |
| .btm | Microsoft BizTalk Map Format |
| .btn | Just Buttons Animated Bitmap Image Format |
| .bto | Bryce Tree Format |
| .btoa | Binary-to-ASCII File Format |
| .btr | Btrieve Database Format |
| .btree | Apple Mac OS HFS+ B-tree |
| .bts | Creative Digital Blaster Digital VCR |
| .btsearch | BitTorrent Search Engine Specification Format |
| .btskin | µTorrent Skin |
| .btst | Norton SystemWorks Info |
| .btt | ICQ Find Users |
| .btu | Diablo BTU Calculator |
| .btw | BarTender Barcode Label Format |
| .btwsendto | Microsoft Windows Bluetooth Related |
| .btx | InMagic Database Term/word Index |
| .bty | Railroad Tycoon 3 Building |
| .bu | Pegasus Mail Temporary |
| .bub | Photobubble |
| .buc | Adobe Photoshop Elements Backup |
| .bud | Pscript Binary PostScript Printer Description Format |
| .buf | Buffer Format |
| .bufferedimage | Java Class |
| .bugsense | BugSense |
| .build | NAnt Build Tool |
| .buildalot2savedgame | Build-a-lot 2 Save Game |
| .buildalot3savedgame | Build-a-lot 3 Saved Game |
| .builder | Builder Script |
| .buildpath | Eclipse XML Build Path Format |
| .buj | Personal Backup Saved Task |
| .bul | Bullseye Data Format |
| .bum | Poser Bump Files Image Format |
| .bun | CakeWalk Audio Bundle Format |
| .bundle | Mac OS X Application Extension |
| .bundledmesh | Battlefield Bundled Mesh |
| .bup | Backup Of DVD Info Format |
| .bur | BuRg3r Source Code Format |
| .burn | Burn For Mac OS X Document |
| .BurnoutParadiseSave | Burnout Paradise Saved Profile |
| .burntheme | Burn For Mac OS X Theme Document |
| .bus | VirtualBus Bus Route Settings Format |
| .bv1 | Corel WordPerfect Overflow |
| .bv2 | Corel WordPerfect Overflow |
| .bv3 | Corel WordPerfect Overflow |
| .bv4 | Corel WordPerfect Overflow |
| .bv5 | Corel WordPerfect Overflow |
| .bv6 | Corel WordPerfect Overflow |
| .bv7 | Corel WordPerfect Overflow |
| .bv8 | Corel WordPerfect Overflow |
| .bv9 | Corel WordPerfect Overflow |
| .bvc | IBM Voice Type Languages Newuser |
| .bvd | BitDefender Vault Format |
| .bvh | Biovision Hierarchy Animation Format |
| .bvi | IBM Voice Type Languages Newuser |
| .bvl | Micrografx Picture Publisher 8 Textures |
| .bvp | Bluevoda Website Builder Format |
| .bvr | Blue Iris Video Format |
| .bvs | BVS Solitaire Collection |
| .bvw | SmartWare Backup Standard View |
| .bvx | OptiTune Install Package |
| .bvxd | OptiTune Manifest |
| .bw | Silicon Graphics Image |
| .bw1 | FMEA Database |
| .bwa | BlindWrite BWA Builder Physical CD Characteristics Format |
| .bwc | BeadWizard Color Palette |
| .bwd | Colin McRae Rally 2 Car Description |
| .bwe | Black And White 2 Environment Data |
| .bwf | Broadcast Wave File Format |
| .bwg | BrainWave Generator Format |
| .bwi | BlindWrite CD/DVD Image Format |
| .bwm | Blaise |
| .bwp | BuRg3r Web Page |
| .bws | BlindWrite Subchannel Data Format |
| .bwt | Blindwrite Control Format |
| .bwu | Blindwrite CD Copier |
| .bww | Bagpipe Music Writer Music Notation Format |
| .bwz | WinImage Batch Configuration |
| .bx | Opera |
| .bxb | BasicX Compiled Project Bytecode |
| .bxi | Blaise |
| .bxl | Accelerated Designs PCB Library Format |
| .bxm | BasicX-24 Basic Express Compiler Map |
| .bxml | Bean XML |
| .bxp | BasicX-24 Basic Express Compiler Module List |
| .bxrc | Configuration |
| .bxu | PictureGear Studio |
| .bxx | BlaxxunContact Format |
| .bxy | NuFX Archive Within A Binary II Envelope |
| .by | PSpice |
| .byu | Movie.BYU Geometry Format |
| .bz | BZIP Compressed File Archive |
| .bz1 | WinTOTAL Automatic Backup |
| .bz2 | Bzip2 Compressed File Archive |
| .bza | Bzip2 Compressed File Archive |
| .bzabw | AbiWord Bzip2 Compressed Document Format |
| .bzip | Bzip Compressed Archive |
| .bzip2 | BZIP Compressed Archive Format |
| .bzm | Business Map |
| .bzn | Star Trek Armada Map |
| .bzp2 | BZIP2 Archive |
| .bzs | BlueZone Script |
| .bzw | BZFlag Map Format |
| .bzz | BuzzBundle Project |
