| Extension | Information |
| B | Applause Batch List |
| B | BASIC Language Source |
| B | Befunge Program |
| B | Brainf*ck Program |
| B | Grand Theft Auto IIISave File (Take-Two Interactive Software, Inc.) |
| B | Limbo Implementation File |
| B | Modula-3 Base Program |
| B | IRIS Editor Shortened Format File (eurobraille) |
| B!K | Flight Simulator Scenery File (Microsoft) |
| B&W | 1st Reader Mono Binary Screen Image |
| B&W | Atari Black and White Graphics |
| B&W | Image Lab |
| B02 | ADP Payroll |
| B1 | 21st Century Mahjong |
| B1 | Progress Database Database File (Progress Software) |
| B16 | PCO Graphic |
| B1J | BookJones |
| B1N | 1st Reader Binary Screen Image |
| B1S | BookSmith |
| B2 | Progress Database Database File (Progress Software) |
| B2D | Brutus2D Source Code File (Pewter Software) |
| B2Z | B2Z dVS Model/Object |
| B30 | Ventura Publisher Printer Font |
| B32 | MS-DOS Bcc file |
| B3D | 3D Builder |
| B3D | BDE Multipath Movie Digital Viewer |
| B3D | Blitz3D/Max/Plus Texture or Mesh File (Blitz Research Ltd.) |
| B3D | Boso View Express Structure Mesh Diagram (Mackoy) |
| B4 | Helix Nuts and Bolts File |
| B4S | Winamp 3+ Playlist |
| B4U | docPointer Visual ReadMe File (docPointer) |
| B5 | CEDICT Chinese/English Dictionary (Erik E. Peterson) |
| B5I | DAEMON Tools |
| B5I | IsoBuster CD/DVD Image File (Container) (Smart Projects) |
| B5L | BlindWrite Ver. 5 File (VSO-Software) |
| B5S | Numerical Controlled Machine File |
| B5T | BlindWrite Ver. 5 File (VSO-Software) |
| B5T | DAEMON Tools |
| B64 | Base 64 MIME-encoded File |
| B8 | PictureMaker Blue Channel Image Data (Cubicomp) |
| B8 | Piclab Raw Graphic File |
| BA$ | MS Compressed BAS Decompress with UNPACK.EXE. |
| BAB | Babble! Data File (Korenthal Associates, Inc, 230 W 13th St, NYC 10011) |
| BAC | Backup |
| BACKPACK | Backpack Word List (Mammoet Software) |
| BACKUP | Ad-Aware Reference File (Lavasoft) |
| BACKUP | ISAPI Loader Backup of Current ISAPI Application (EGGcentric) |
| BAD | Brutus Application Definition File |
| BAD | Oracle BAD File |
| BAD | Rime Mailer Address File |
| BAF | Infinity Game Engine Script (BioWare Corp.) |
| BAG | AOL 6 Organizer (America Online, Inc.) |
| BAG | Emperor: Battle for Dune Archive |
| BAG | AOL Instant Messenger Buddy List (America Online, Inc.) |
| BAG | OS/2 Netfinity Manager Sysinfo File |
| BAG | PMMail Mail Index File |
| BAG | NoX |
| BAG | Bag Archive File |
| BAH | Infinity Game Engine (BioWare Corp.) |
| BAK | Backup |
| BAL | BAL Borland Programming Language Source |
| BAL | Ballade Music Score |
| BAM | Infinity Game Engine Animation and Multi-frame Graphics (BioWare Corp.) |
| BAM | Infinity Game Engine Zlib Compressed Animation and Multi-frame Graphics (BioWare Corp.) |
| BAM | OHRRPGCE Music File (Hamster Republic) |
| BAM | Bob's Adlib Music |
| BAM | Bravo! Archived Media (Thought Studios, Inc.) |
| BAN | Sierra Print Artist Banner |
| BAN | Creatacard Banner Project (Broderbund) |
| BAND | GarageBand Song (Apple Computer, Inc.) |
| BAR | dBASE Application Generator Horizontal Menu Object |
| BAR | Age of Mythology |
| BAS | BASIC Source Code |
| BAS | VBDOS Pro 1.0 Source |
| BAS | QuickBASIC Extended v7.1 Source |
| BAS | HBasic Source Code |
| BAS | e.Report Designer Actuate Basic Source (Actuate Corporation) |
| BAT | Batch Processing (Microsoft) |
| BAV | The Bat! E-mail Client Anti-Virus File (RITLABS) |
| BAY | Kodak/Roper Bayer Picture Sequence |
| BB | Blitz3D/Max/Plus Source Code (Blitz Research Ltd.) |
| BB | Papyrus Database Backup |
| BB | Starfleet Battles DOS Game |
| BB | Art-lantis Billboard Management File (ABVENT) |
| BB | BrowserBob Project File (BrowserBob weblications) |
| BB2 | XBBS-OS/2, XGROUP, AV and ZTree Archiver Control File |
| BBC | BBC BASIC for Windows File (R. T. Russell) |
| BBC | Babya Photo Workshop Color Collection (Babya Software Group) |
| BBE | Brainbloom Document Exchange File (Gael Limited) |
| BBF | FRAMES Body Burden Concentration File |
| BBG | CyberSports for Basketball Game File (CyberSports, Inc.) |
| BBK | WWTBAM Game Component |
| BBL | TeX/BibTeX Bibliographic Reference File |
| BBM | Deluxe Paint Image File |
| BBM | BDBZM (Project BDBZM) |
| BBMA | Bonzibuddy |
| BBNNG | BBN BitGraph Terminal Display Pixel Data (DPD) Sequence Bitmap |
| BBP | Bezier Surface File |
| BBP | BitBeamer Split File |
| BBQ | BitBeamer Transfer Queue File |
| BBRKPUZZLE | BrainsBreaker Puzzle (Juan Trujillo) |
| BBRKSAVE | BrainsBreaker Started Puzzle Status (Juan Trujillo) |
| BBS | Bulletin Board System Text |
| BBS | FTN Software Hudson-style Messagebase |
| BBT | CyberSports for Basketball Team File (CyberSports, Inc.) |
| BBZ | Bitblaze Audio File |
| BC | Mikmak 203 file |
| BC | Sierra Print Artist Business Card |
| BC! | BitCommet Incomplete Download (BitComet.com) |
| BC3 | BCC 3 Make File |
| BC3 | Fiebdc-3 Format File |
| BCA | Railroad Tycoon 3 Building (PopTop Software Inc.) |
| BCA | Allplan 2005 Backup Catalog File (Nemetschek A.G.) |
| BCB3 | BC3 Make File |
| BCC | C++ File/Makefile (Borland Software Corporation) |
| BCC | Calendar Creator 8 Collection |
| BCD | Cosmi Business Card Maker |
| BCD | Turbo Pascal DOS File (Borland Software Corporation) |
| BCD | Binary Cartographic Data File |
| BCD | OfficePrinter Document (Moss Bay Software) |
| BCF | ConfigSafe Snapshot Index |
| BCF | The Sims 3D Body Mesh File (Electronic Arts (Maxis)) |
| BCH | Datalex Entry Point 90 Data File (Phoenix Software) |
| BCH | dBASE Application Generator Batch Process Object |
| BCI | Advisor Computer Profile Report (Belarc) |
| BCK | Backup |
| BCK | VMS/VAX BaCKup |
| BCKP | Ad-Aware Quarantine File (Lavasoft) |
| BCM | Works Communications File (Microsoft) |
| BCM | Compaq Easy Access Keyboard Driver |
| BCMR | BC Framer (Boise Cascade) |
| BCN | Business Card Pro Design |
| BCO | Bitstream Fontware |
| BCO | MicroSim PCBoard Backward Engineering Change Order |
| BCP | C++ Makefile (Borland Software Corporation) |
| BCP | Business Card Designer Plus Design File (CAM Development) |
| BCS | Infinity Game Engine Compiled Script (BioWare Corp.) |
| BCS | Windows95 Browse Information |
| BCS | Brian's Compression Shell (BCS) Image Animation/Video Shell |
| BCT | Business Card Designer Template |
| BCT | Clarion for Windows Backup Dictionary (SoftVelocity) |
| BCW | C++ Version 4.5 Environment Settings (Borland Software Corporation) |
| BD4 | West Point Bridge Designer Ver. 4 Bridge Design |
| BDB | Works Database File (Microsoft) |
| BDB | CHASE Evaluation and Audit System Executable (Health And Safety Technology And Management Ltd.) |
| BDBZM | BDBZM (Project BDBZM) |
| BDC | Lingvo dictionary |
| BDC | West Point Bridge Designer |
| BDE | Borland Database Engine (Borland Software Corporation) |
| BDE | Pro/ENGINEER Temporary File (PTC) |
| BDF | Backup To CD-RW Backup Definition File |
| BDF | Bupdate Binary Update File |
| BDF | Egret Data File |
| BDF | Glyph Bitmap Distribution Format (Adobe) |
| BDF | NuGraf Scene file |
| BDF | West Point Bridge Designer |
| BDF | X11 Bitmap Distribution Format |
| BDF | Brother BES-100E Embroidery Software File (Brother Industries, Ltd.) |
| BDF | RD Birthday Reminder Data File (Christian Weiske) |
| BDF | Quartus II Block Design File (Altera Corporation) |
| BDF | UNIX Font File |
| BDF | TXRDWIN X-ray Diffraction Pattern (Omni Scientific Instruments, Inc.) |
| BDG | Badge Designer 2000 Photo ID |
| BDI | Pro/ENGINEER Temporary File (PTC) |
| BDL | OneSpace Designer Bundle (CoCreate) |
| BDM | Pro/ENGINEER Temporary File (PTC) |
| BDR | Publisher Border (Microsoft) |
| BDSPROJ | Developer Studio Project File (Borland Software Corporation) |
| BDT | Lingvo Dictionary |
| BDW | Budget For Windows Data File (Snowmint Creative Solutions LLC) |
| BDX | BarBack Drink Exchange File |
| BDX | FUSE Science Pipeline Bad Data File |
| BDX | JavaBib Index File |
| BEA | Beamer Song File (The Beamer Project) |
| BEC | Break Even Calculator |
| BED | InfoSnorkel Blue Elephant Definition |
| BEE | Beeline-AIR System File |
| BEE | The Bee Archiver Compressed Archive |
| BEF | Boomi Integration Platform Setup Information (Boomi, Inc.) |
| BEL | Belon Compressed Archive |
| BEL | HPXView Binary Event Log Archive (Haliplex Communication Systems) |
| BEL | Beamer Layout File (The Beamer Project) |
| BEN | Syssoft Sandra File |
| BEP | Beamer Playlist (The Beamer Project) |
| BER | German Bericht Report File |
| BEX | BOOM Extensions To Dehacked |
| BEX | British National Bibliography File |
| BEX | Kashmir 3D Transparent Color Definition |
| BEX | Pretty Good Privacy (PGP) Binary Extracted Public Key (PGP Corporation) |
| BEXPK | Pretty Good Privacy (PGP) Binary Extracted Public Key (PGP Corporation) |
| BEZ | Bezier Surface File |
| BEZ | Bitstream Fontware |
| BF | Befunge Program |
| BF | Brainf*ck Program |
| BF | Beyond Good & Evil Game Archive (Ubi Soft Entertainment) |
| BF2 | Bidfax 2000 SE Database |
| BF2 | Bradford 2 Font |
| BFA | Blowfish-encrypted File |
| BFB | Ralcgm File |
| BFC | Windows 95 Briefcase File |
| BFF | AIX Backup File Format |
| BFF | WorldToolKit Neutral File Format |
| BFFM | B17 Flying Fortress Game File |
| BFL | Big Flexible Line Interpretation (C64) Bitmap |
| BFL | Colin McRae Rally 2 Data File |
| BFL | yBook eBook (Spacejock Software) |
| BFLI | Big Flexible Line Interpretation (C64) Bitmap |
| BFM | UNIX Font Metrics File |
| BFR | NI Observer Capture File |
| BFS | Tivoli Storage Manager File (IBM) |
| BFX | BitFax Document (Bitware) |
| BG | Backgammon for Windows Game File (Microsoft) |
| BG | Lotus Agenda File |
| BGA | OS/2 Bitmap Graphic Array (IBM) |
| BGB | Chat Background Graphic (Microsoft) |
| BGDB | Global Virtual Accademy E-Learning File |
| BGI | Borland Graphic Interface (Borland Software Corporation) |
| BGL | Babylon Glossary File (Babylon.com Ltd.) |
| BGL | Flight Simulator Scenery File (Microsoft) |
| BGM | Jane's Combat Simulations F-15 |
| BGO | BigOven Recipe Card (sdmventures) |
| BGT | Quicken 2002 Internet Common File |
| BGT | Graphic Accounts Budget Data (FKJ Software) |
| BGV | BonanzaGraf |
| BGW | Final Fantasy XI Music (Square Enix Co., LtdSquare Enix Co., Ltd) |
| BGX | BC45 BGI File |
| BH | BlackHole Archive Format File |
| BHF | pcAnywhere Host File (Symantec) |
| BHI | Partminer Lib file |
| BHL | Partminer Lib file |
| BHS | Rise of Nations Script (Microsoft) |
| BHTML | BabuHTML Embedded Software File |
| BHX | BinHex Compressed File ASCII Archive |
| BI | Binary File |
| BI | Progress Database Before Image File (Progress Software) |
| BI | Quick Basic or Visual Basic for DOS Include File (Microsoft) |
| BI$ | MS Compressed BI Decompress with UNPACK.EXE. |
| BI7 | Rukus 110 File |
| BIB | Bibliography |
| BIB | JavaBib BibTeX File |
| BIB | Papyrus Database |
| BIB | TeX/BibTeX Literature Database |
| BIBTEX | BibTeX Document |
| BIC | Civilization III Scenario |
| BIC | Neverwinter Nights Character Sheet (Bioware) |
| BID | BidMaker 2002 |
| BIE | JBIG File |
| BIF | Baldur's Gate Archive |
| BIF | Binary Information File |
| BIF | GroupWise Initialization File |
| BIF | Image Capture Board Binary Black & White Image |
| BIF | BioWare Infinity Engine Archive of Resources (BioWare Corp.) |
| BIF | Planescape: Torment Archive |
| BIF | UltraISO Boot Information File (EZB Systems, Inc.) |
| BIF | byLight Graphic |
| BIF | MagicISO Boot Information File (MagicISO Inc.) |
| BIFF | XLITE 3D file |
| BIFF | BioWare Infinity Engine Archive of Resources (BioWare Corp.) |
| BIG | Cartes Michelin |
| BIG | Chinese Text |
| BIG | Fifa World Cup Game File |
| BIG | Homeworld (Sierra) |
| BIG | Electronic Arts Game MOD File (Electronic Arts, Inc.) |
| BIG | Home World 2 SGA Archive (Relic Entertainment Inc.) |
| BIG5 | Chinese Text |
| BIK | Bink and Smacker Game Video File Codec (RAD Game Tools, Inc.) |
| BIK | BioCharter Profile Backup |
| BIL | ArcView Image File (ESRI) |
| BIN | Binary File |
| BIN | MacBinary Archive Format Often used on Macintosh. |
| BIN | Micrografx Designer 7 Project Image |
| BIN | SGI Powerflip |
| BIN | CDRWin CD Image File |
| BIN | Linux Executable |
| BIN | TenCORE Plug-in Helper Application (TenCORE) |
| BIN | AVG Anti-Virus Update File (Grisoft, Inc.) |
| BIO | BioCharter Profile |
| BIO | Infinity Game Engine Character Biography (BioWare Corp.) |
| BIO | OS/2 Bios File |
| BIO | BioArc Compressed Archive |
| BIP | ArcView Image File (ESRI) |
| BIT | Worms Armageddon Imported Map |
| BIT | Worms World Party Imported Map |
| BIT | X11 Bitmap Image |
| BIT | Xilinx Integrated Software Environment Bitstream File (Xilinx, Inc.) |
| BIU | BidMaker 2002 Update |
| BIX | BIX Archiver Compressed Archive |
| BIX | Index to a .BIB BibTeX Bibliography Database |
| BIX | Civilization III Scenario |
| BIZ | Print Shop Business Card File (Broderbund) |
| BIZ | Creatacard Business Card Project (Broderbund) |
| BIZ | ShowBiz Project File (ArcSoft, Inc.) |
| BIZ | BIZ dVS Model/Object |
| BIZ | PrintMaster Gold Document (Broderbund) |
| BJF | NTI Backup NOW! File |
| BJG | DESQview (Symantec) |
| BJK | Scanner Recognita file |
| BJL | BJL Business Systems Active Translation Document (The BJL Group) |
| BJO | Tabrite Banjo Tablature (Janet Davis Music) |
| BK | Backup |
| BK | FrameMaker BookFile Document (Adobe) |
| BK | JetFax Faxbook File |
| BK | LinguAssist File |
| BK! | Backup |
| BK$ | Backup |
| BK1 | Bach Preludes and Fugues MIDI akmi Source, Book 1 |
| BK1 | Backup |
| BK1 | VirtuaGirl Graphics Container (Totem Entertainment) |
| BK2 | Bach Preludes and Fugues MIDI akmi Source, Book 2 |
| BK2 | Backup |
| BK2 | VirtuaGirl Graphics Container (Totem Entertainment) |
| BK3 | Backup |
| BK3 | VirtuaGirl Graphics Container (Totem Entertainment) |
| BK4 | Backup |
| BK5 | Backup |
| BK6 | Backup |
| BK7 | Backup |
| BK8 | Backup |
| BK9 | Backup |
| BKC | Collectorz.com Book Collector Book Collection Data (Collectorz.com) |
| BKC | Backup4all Backup Catalog File (Softland) |
| BKF | Moto Racer Archive |
| BKF | WindowsXP Backup Utility Backup Set (Microsoft) |
| BKG | Background File |
| BKG | UWXAFS Binary Format Data File |
| BKI | Backup Index |
| BKI | IBM BookManager Backup Index |
| BKI | IBM Softcopy Reader (Bookmanager) Bookshelf (and Book) Index File (IBM) |
| BKP | Backup |
| BKR | Bruker Aspect NMR Data File |
| BKR | ReplaceEm Fileset (Custom Fit Software) |
| BKS | BookManager Read Bookshelf (IBM) |
| BKS | Works Spreadsheet Backup (Microsoft) |
| BKS | Windows 2000 Scheduled Backup Script (Microsoft) |
| BKS | IBM Softcopy Reader Bookmanager Book File (IBM) |
| BKT | Zortech 3 tools Samples File |
| BKU | Timeslips Backup (Peachtree Software) |
| BKW | FontEdit Fontset Mirror Image |
| BKY | bookkey Bookmark/Keyword Data (Michael Valentiner-Branth) |
| BL | Binary Linework TIFF Bitmap |
| BLA | Black Color Separation (Adobe) |
| BLA | Blat E-mail |
| BLB | DreamWorks Resource Archive |
| BLB | Blorb Game Resource Package |
| BLB | ACT! Database File (Best Software CRM Division) |
| BLC | BIACORE Instruments and BIAlite Project (Biacore) |
| BLD | ACT! (Best Software CRM Division) |
| BLD | BASIC Bload Graphics |
| BLD | Developer Studio MAK (Microsoft) |
| BLD | MegaPaint |
| BLD | RealFlight Radio Control Airplane Description (Knife Edge Software) |
| BLD | VersaPro Block Build Info |
| BLD | Weinberger Picture Sequence |
| BLD | Yoot Tower Saved (Game) Building (Sega) |
| BLD | EnergyPro (EnergySoft, LLC) |
| BLD | My Personal Programmer Project File (M:Pact Technologies) |
| BLE | Photoline4 Blends file |
| BLE | BIAevaluation Ver 2.x Project (Biacore) |
| BLEND | Blender 3D File |
| BLEND | Blender Publisher Data File (Stichting Blender Foundation) |
| BLF | Beast 2.02 Trojan File |
| BLF | BIACORE Instruments and BIAlite Project (Biacore) |
| BLF | Telerate Workspace File |
| BLF | BancTec Scanner Driver (Kofax) |
| BLF | ObjectStore Distribution File (Franz Inc.) |
| BLF | Advanced Computer Architecture Car Simulation |
| BLF | DriveBlockEditor Function Block Programming Data (Rockwell Automation) |
| BLF | Rally Online Car Texture File (GameSpy Industries) |
| BLG | ARCSOLO Backup Log |
| BLG | BibTeX Log |
| BLG | MicroSim PCBoard Backward ECO Log File |
| BLG | Windows Binary Performance Log |
| BLI | BLINK Archiver Archive (De Trans Software) |
| BLK | Amiga IFF (Amiga) |
| BLK | Lightscape Block Library |
| BLK | ProWORX Nxt Block Data (Schneider Electric) |
| BLK | VersaPro Block |
| BLK | Wavefront Image (Alias) |
| BLK | WordPerfect Temporary File (Corel Corporation) |
| BLK | Win32Forth Block Data |
| BLL | INPRISE Format Language Library (Borland Software Corporation) |
| BLL | VBS/European-A Worm |
| BLN | Rise of Nations Campaign Media File (Microsoft) |
| BLOB | Cosmic Blobs Model (SolidWorks Corporation) |
| BLP | Blizzard Game Picture (Blizzard Entertainment) |
| BLR | BIACORE Instruments and BIAlite Project (Biacore) |
| BLS | BIACORE Instruments and BIAlite Project (Biacore) |
| BLS | Brush Lettering Saved Brush Lettering Style (EK Success, Ltd., pcCrafter, Inc.) |
| BLT | AOL Instant Messenger (AIM) Saved Buddy List File (America Online, Inc.) |
| BLT | Wordperfect for DOS (Corel Corporation) |
| BLT | CATC Merlin Bluetooth Trace Files (Computer Access Technology Corporation (CATC)) |
| BLW | ArcView World File For BIL Image (ESRI) |
| BLY | Fifa World Cup Game Art Loadgame file. |
| BLZ | Bitmap Graphic |
| BLZ | Blazon Heraldic Shield |
| BLZ | Emblaze.Creator File |
| BLZ | Serial Number File |
| BLZ | Twinkle Bulbs Bulb File |
| BLZ | N-Gage Game File (Nokia) |
| BM | X Windows System Bitmap |
| BM$ | Modem Bitware Fax disk2 file |
| BM1 | Apogee BioMenace Data |
| BM2 | Subspace/Continuum Graphic |
| BMB | SLICS Bounding Box Information |
| BMB | Pro/ENGINEER Temporary File (PTC) |
| BMC | IBM Voice Type languages Newuser File |
| BMC | Embroidery Graphic File |
| BMD | Mu Online Data File (WEBZEN, Inc.) |
| BME | Beatmania Music Simulator File (Konami Broadcasting) |
| BMF | Corel Flow Image File (Corel) |
| BMF | FloorPlan Project File (IMSI (International Microcomputer Software Inc.)) |
| BMF | BMF Bitmap |
| BMF | BrainMine Mind Map (Neural Matters Limited) |
| BMG | Bert's Dinosaurs File |
| BMI | Blue Martini Import File |
| BMI | Buzz Instrument |
| BMI | 3ds Max Executable (Autodesk, Inc.) |
| BMK | BMC Software Patrol Icon File |
| BMK | Help Bookmark |
| BML | Bean Scripting Framework (BSF) File |
| BML | BPM Studio Skin Bitmap (ALCATech) |
| BML | Alpha Five Image Library File (Alpha Software, Inc.) |
| BMM | Tacmi Pixia Palette File |
| BMP | Infinity Game Engine Palette Information (BioWare Corp.) |
| BMP | Windows OS/2 Bitmap Graphics |
| BMP24 | Bitmap Graphic |
| BMPENX | egis Encrypted BMP File (HiTRUST Inc.) |
| BMS | Backup Magic Backup Set |
| BMS | BeMusic Script |
| BMS | Beatmania Music Simulator File (Konami Broadcasting) |
| BMT | Ami Pro Button Image (IBM) |
| BMT | Alpha Five Image Library File (Alpha Software, Inc.) |
| BMU | Music/Sound File |
| BMW | Buzz Music File with Waves |
| BMX | Buzz Music File |
| BMX | Siemens Mobile Phone Animation (Siemens) |
| BMX | BMXdesign Extended Bitmap Graphic (Container) (HEIDENHAIN) |
| BMX | Alpha Five Image Library File (Alpha Software, Inc.) |
| BMZ | Compressed BMP File |
| BMZ | Demon Stalkers: Raid on Doomfane |
| BM_ | Mumath 30 File |
| BM_ | WebCD Fread File |
| BN | AdLib Instrument Bank |
| BN2 | Bojanov Encryptor Encrypted File (Bojanov Software) |
| BN7 | Ox Object-Oriented Matrix Programming Language PcGive 7 Data File |
| BNC | Bojanov Encryptor Encrypted File (Bojanov Software) |
| BND | Flight Simulator Panels File (Microsoft) |
| BND | Typequick File |
| BND | DB2 Bind File |
| BNF | IBM Voice Type Languages Map File |
| BNG | RANGER.EXE |
| BNK | AdLib Instrument Bank |
| BNK | Bink Compressed Video/Audio File |
| BNK | SimCity Game File (Electronic Arts, Inc.) |
| BNK | ExamView Question Bank (FSCreations, Inc.) |
| BNL | MicroSim PCBoard Netlist File For The Board Layout |
| BNR | Banner - Poster Graphic Banner |
| BNR | Binary News Reader File |
| BNSKIN | BeatNik Clock Skin (Something Decent) |
| BN_ | Ntgraph Ze32v215 file |
| BOA | BOA Constrictor Archiver Compressed Archive |
| BOB | Bob Raytracer |
| BOB | BobDown Downloading Program |
| BOCHSRC | Bochs Configuration File (The Bochs Project) |
| BOD | Data Designer Ddbac File |
| BOD | Roland Garros Tennis Terrain File |
| BOE | Outlook Express Backup File (Microsoft) |
| BOF | IBM Voice Type Language Task Enroll File |
| BOI | Botje Bot-file (TNHteam) |
| BOL | Booasm Compressed Archive Library (Microsoft) |
| BOM | MicroSim PCBoard Bill of Materials |
| BOM | Orcad Schematic Capture Bill of Materials File |
| BOM | Softshare Delta Business Object Model |
| BOM | Pro/ENGINEER Temporary File (PTC) |
| BOM | Bill of Materials File |
| BONK | BONK Lossless/Lossy Audio Compressor |
| BOO | Book |
| BOO | Compressed Archive File |
| BOO | IBM BookManager Book |
| BOO | Image File |
| BOO | Kermit Protocol Binary Bootstrap File |
| BOOK | FrameMaker Book (Adobe) |
| BOOK | ICE Book Reader Book File (ICE Graphics) |
| BOOT | InstallShield (InstallShield Software Corporation) |
| BOOTSKIN | BootSkin Windows Boot Skin (Stardock Corporation, Inc.) |
| BORLAND | C Makefile (Borland Software Corporation) |
| BOS | Brotherhood of Steel Compressed File |
| BOT | Frogbot Editor |
| BOT | LinkBot document |
| BOT | Robot Arena: Design & Destroy Robot (Gabriel Group, Inc.) |
| BOT | Soldat Bot Information File (Michal Marcinkowski) |
| BOW | Back Orifice 2K Workspace |
| BOX | Lemmings Revolution Archive |
| BOX | Notes Mailbox |
| BOX | ThrottleBox Multimedia Viewer |
| BOX | Vbox Helper Application File (Aladdin Knowledge Systems) |
| BOX | Calypso Email Mailbox (Rose City Software) |
| BOX | Foxmail E-Mail Box |
| BOX | VTrain (Vocabulary Trainer) Box File (Paul Raedle) |
| BOXR | Boxerjam Interactive Game System |
| BOZ | BZIP Over ZIP Compressed File Archive |
| BP | Binary Picture TIFF Bitmap |
| BP | BankPerfect Accounts File (Fabio Chelly) |
| BPC | BuildPro File |
| BPC | Business Plan Toolkit Chart |
| BPD | BizInt Smart Charts for Patents Data Transfer Format (BizInt Solutions) |
| BPD | FARSITE Burn Period File (The Fire Sciences Lab (FiSL)) |
| BPD | Cash Compass Plan (Palo Alto Software, Inc.) |
| BPD | Data Designer Database Backup File |
| BPD | PCIScope PCI and ISA PnP Subsystem Information (APSoft) |
| BPD | Pscript Binary PostScript Printer Description File |
| BPD | catDB Template Property Dictionary |
| BPD | DTLplot Beadpull Data File |
| BPD | Business Plan Pro Business Plan Data (Palo Alto Software, Inc.) |
| BPF | Cash Compass Table Formatting (Palo Alto Software, Inc.) |
| BPG | Borland Project Group (Borland Software Corporation) |
| BPI | IBM Voice Type languages Newuser file |
| BPJ | Bravo! Project (Thought Studios, Inc.) |
| BPK | C++ Builder Package File (Borland Software Corporation) |
| BPKEY | Blender Publisher License Key (Stichting Blender Foundation) |
| BPL | AutoCAD R2000 Batch Plot List (Autodesk, Inc.) |
| BPL | Delphi Library (Borland Software Corporation) |
| BPL | Winamp Ver 3 Playlist File (Nullsoft) |
| BPLIB | BrilliantPhoto Photo Library File (Brilliant Labs, Inc.) |
| BPM | Brazil r/s Photon Map Storage File (SputterFish, LLC) |
| BPP | Clarion for Windows Backup Application (SoftVelocity) |
| BPP | MUSICMATCH Burner Plus Project |
| BPP | Taskmaster Batch Pilot Project (Datacap Inc.) |
| BPR | BackupXpressPro Project File |
| BPR | C++ Builder 6 Project (Borland Software Corporation) |
| BPR | Reference Count 01 File |
| BPS | Bulletproof FTP Settings |
| BPS | Business Plan Toolkit |
| BPS | Works Document (Microsoft) |
| BPS | XMap Flight Plan or Flight Plan Statistic File (Delorme) |
| BPT | Corel Bitmap Master File |
| BPT | Belarc Product Key (Belarc) |
| BPV | BallPark Business Valuation Valuation Scenario File (BulletProof Business Plans) |
| BPW | ArcView World File For BIP Or BMP Images (ESRI) |
| BPX | Lumena BigPix |
| BPX | Truevision Targa Bitmap |
| BPX | BusiPlan File (Manager-Pro) |
| BQW | ArcView World File For BSQ Image (ESRI) |
| BQY | BrioQuery File |
| BR | Bridge Script |
| BR | Omnis7 Data (Omnis Software) |
| BR | The Playa File |
| BR1 | Wincmd Fle |
| BR3 | Bryce 3D Scene File (Corel) |
| BR4 | Bryce 4 (Corel) |
| BR5 | Bryce 5 (Corel) |
| BRAIN | Msdev Common Addins File |
| BRC | Bryce 2 Scene File (Corel) |
| BRC | Onset Design Briefcase Briefcase (Onset Design) |
| BRD | EAGLE Layout Editor Board File (CadSoft Computer GmbH) |
| BRD | Allegro (Cadence Design Systems) |
| BRD | BizInt Smart Charts for Pharmaceuticals Data Transfer Format (BizInt Solutions) |
| BRD | RPG Toolkit Board Design File (Christopher Matthews) |
| BRD | Winning Bridge Saved Hand (Gerald Wilson) |
| BREP | Boundary Representation File Format |
| BREP | Open CASCADE 3D Model File (Open CASCADE Company) |
| BRF | Braille ASCII File |
| BRF | Brief |
| BRF | Duxbury Braille Translator Cross Platform Braille File (Duxbury Systems, Inc.) |
| BRI | Basic Rate Interface File |
| BRI | FirstClass |
| BRK | Brooktrout Fax-Mail File |
| BRK | The Brake! Mailer REXX Script |
| BRL | Ballistic Research Laboratory CAD |
| BRLCAD | Ballistic Research Laboratory CAD |
| BRN | PersonalBrain Data (Brain) File (TheBrain Technologies Corp.) |
| BRN | BrainStorm Data File (Brainstorm Software Ltd) |
| BRN | yBook Compiled eBook (Spacejock Software) |
| BRO | BR-532 Digital Studio |
| BRO | Tree Professional Broadleaf Creator File |
| BRO | Creatacard Booklet/Brochure Project (Broderbund) |
| BRO | Embroidery File |
| BRP | Tree Professional Broadleaf Creator Image |
| BRS | Corel Painter Brush File |
| BRS | RoboHELP Browse Sequence |
| BRS | Batchrun Batch File (Outer Technologies) |
| BRT | Brooktrout Fax-Mail File |
| BRT | Micrografx System4 Browser file |
| BRT | PeoplePC Install Script (PeoplePC, Inc.) |
| BRU | Brutus Restore File |
| BRU | Photoline4 Brushes File |
| BRUSH | Xerox Doodle Brush File |
| BRW | Application File Associated with financial institution(s) loan applications. |
| BRX | Multimedia Browsing Index |
| BRZ | DbBRZ File |
| BS | Infinity Game Engine Compiled Script (BioWare Corp.) |
| BS | Printfox/Pagefox Bitmap |
| BS1 | Apogee Blake Stone Data |
| BS2 | Basic Stamp 2 Code File |
| BSA | BSARC Compressed Archive |
| BSB | MapInfo Sea Chart |
| BSB | SWAT Sub-basin Output File |
| BSC | Apple II Compressed Archive (Apple Computer, Inc.) |
| BSC | Boyan Script |
| BSC | Developer Studio Browser File (Microsoft) |
| BSC | Fortran Pwbrmake Object |
| BSC | Source Browser Database |
| BSCS | Strategy2Act Balanced Scorecard File (AKS-Labs) |
| BSCT | Strategy2Act Balanced Scorecard Strategy File (AKS-Labs) |
| BSD | FacetWin Bitwise Backup Set (FacetCorp) |
| BSE | CRiSP Harvest File |
| BSF | BadukSearch/BadukTracer Selected Game File |
| BSF | Bridge-Soft Quarterly File |
| BSF | JCanyon: Grand Canyon for Java DEM File |
| BSF | Rainbow Six: Rogue Spear Buildspace File (Red Storm Entertainment, Inc.) |
| BSH | BeanShell Script |
| BSI | BSPlayer Configuration |
| BSK | Bryce 4 File (Corel) |
| BSL | BSPlayer Configuration |
| BSN | MIDI File |
| BSN | BSA Packing Program Archive (PhysTechSoft Ltd.) |
| BSP | arahnoWare Enterprise Sever 6 BSP Code Editor |
| BSP | Half-life/TFC/CS Map |
| BSP | Quake Map (id Software) |
| BSP | Star Trek Elite Force Map File (Raven Software) |
| BSP | Valve Game Map File (Valve Corporation) |
| BSP | Getic 3D Scene/Model File |
| BSP | Steam Source SDK Compiled Game Map File (Valve Corporation) |
| BSP | BestAddress HTML Editor Site Project File (Multimedia Australia Pty. Ltd.) |
| BSQ | Apple II BINSCII-encoded (Apple Computer, Inc.) |
| BSQ | ArcView Image File (ESRI) |
| BSQ | Oracle Control File |
| BSQ | BCDown Download |
| BST | BibTeX Style File |
| BST | Star Trek: Birth of the Federation Structure/Ship Info File |
| BSU | Brindys BriTray |
| BSV | BASIC Bsave Graphics |
| BSY | FTN Soft Busy Flag |
| BSY | VTrain (Vocabulary Trainer) Learning Cardfile (Paul Raedle) |
| BSZ | BSplayer Compressed Skin File (BST2K Networks) |
| BS_ | Bookshelf Find Menu Shell Extension (Microsoft) |
| BT | VTBuilder Binary Terrain |
| BT3 | Control Runner Button Configuration File (MomSoft) |
| BTAB | Base Guitar Tabulature |
| BTC | Becker Tools Compressed Archive |
| BTF | Brother Scanner File |
| BTG | FlightGear Scenery File (The FlightGear Crew) |
| BTL | Inmos BooTabLe File |
| BTL | INPRISE Format Language Library (Borland Software Corporation) |
| BTL | American Civil War File (Interactive Magic) |
| BTL | Pokmon NetBattle Battle Replay File (Smogon) |
| BTM | 4DOS Batch To Memory Batch File |
| BTN | ButtonWare File |
| BTN | JustButtons Animated Bitmap (Lincoln Beach Software) |
| BTO | Baytex Organix! 2001 Language Kit |
| BTOA | Binary-to-ASCII Format |
| BTR | Btrieve Database File (Pervasive Software Inc.) |
| BTR | FrontPage Binary-Tree Index (Microsoft) |
| BTS | Creative Digital Blaster Digital VCR File |
| BTT | ICQ Find Users File (ICQ Inc.) |
| BTW | Steuer2001 File |
| BTW | BarTender Barcode Label (Seagull Scientific, Inc.) |
| BTX | DB/TextWorks Database Term and Word Indexes |
| BTX | SEEDIS Index |
| BTX | BibTeX Document |
| BTY | Railroad Tycoon 3 Building (PopTop Software Inc.) |
| BU | Pegasus Mail Temporary File (David Harris) |
| BUB | Ipix Spherical Panorama |
| BUB | Photobubble File |
| BUD | Quicken Backup |
| BUF | WinXL File |
| BUFR | Binary Universal Form for the Representation |
| BUFR | Meteorological Data |
| BUG | Bug (Problem) File |
| BUGS | Generally Bugs File |
| BUL | Holiday Lights Screen Saver Bulb File |
| BUL | Capella Report Card Data File (Castor & Pollux Software Inc.) |
| BUM | Poser Bump |
| BUN | Cakewalk Audio Bundle File (Cakewalk) |
| BUN | Monkey Island 3 |
| BUNDLE | iMovie 3 Plug-in Bundle (Apple Computer, Inc.) |
| BUP | DVD Info File Backup |
| BUP | Brother Embroidery System File |
| BUP | CD Indexer |
| BUP | PC-Bibliothek Update File |
| BUP | Softcode Tracker Contact Manager Backup |
| BUS | Netmino File |
| BUT | Buttons! Button Definition |
| BUY | Movie Data File |
| BV1 | WordPerfect Overflow File (Corel Corporation) |
| BV2 | WordPerfect Overflow File (Corel Corporation) |
| BV3 | WordPerfect Overflow File (Corel Corporation) |
| BV4 | WordPerfect Overflow File (Corel Corporation) |
| BV5 | WordPerfect Overflow File (Corel Corporation) |
| BV6 | WordPerfect Overflow File (Corel Corporation) |
| BV7 | WordPerfect Overflow File (Corel Corporation) |
| BV8 | WordPerfect Overflow File (Corel Corporation) |
| BV9 | WordPerfect Overflow File (Corel Corporation) |
| BVC | IBM Voice Type Language Newuser File |
| BVH | Biovision Motion File |
| BVI | IBM Voice Type Language Newuser File |
| BVL | Micrografx Picture Publisher 8 Textures File |
| BVS | BVS Solitaire Collection |
| BW | Silicon Graphics Raw Black and White Bitmap (Silicon Graphics, Inc.) |
| BW1 | Byteworx FMEA2 FMEA Database (Byteworx Inc.) |
| BWA | BlindWrite CD Image (VSO-Software) |
| BWB | Visual Baler Spreadsheet File |
| BWC | BeadWizard Color Palette (Black Hills Software) |
| BWD | Rally Online Car Description File (GameSpy Industries) |
| BWI | BlindWrite (VSO-Software) |
| BWP | BeadWizard Pattern (Black Hills Software) |
| BWP | Book Writer Project |
| BWR | Kermit Beware Bug List |
| BWS | BlindWrite (VSO-Software) |
| BWT | BlindWrite CD Image File (VSO-Software) |
| BWT | CDmage Table of Contents |
| BWU | BlindWrite (VSO-Software) |
| BWV | Business Wave File |
| BWZ | WinImage Batch Configuration File |
| BXB | BasicX Compiled Project Bytecode (NetMedia, Inc.) |
| BXD | Broken Cross Disk Manager Database (Kevin Fucik) |
| BXF | Man's Best Friend Software Breeder Exchange Format |
| BXM | BX-24 Basic Express Compiler Map |
| BXP | BootXP File |
| BXP | BX-24 Basic Express Compiler Module List |
| BXRC | Bochs Configuration File (The Bochs Project) |
| BXX | blaxxun Contact |
| BY | Spice Pspice File |
| BYO | CartoExploreur Cartographic Map (Bayo) |
| BYU | Movie File |
| BZ | Bzip UNIX Compressed File |
| BZ1 | WinTOTAL Automatic Backup (a la mode, inc.) |
| BZ2 | Bzip 2 UNIX Compressed File |
| BZ2 | ZPoc Christian Music Networks User File List (ZPoc) |
| BZA | BZA Compressed Archive |
| BZF | Textures and Other Information |
| BZN | Star Trek Armada Map File |
| B_T | Eru/erd File |
| B_W | 1st Reader Mono Binary Screen Image |
| B_W | Atari/Macintosh Black and White Graphic |
| B_W | Image Lab |
| B~K | Backup |