| Extension | File Type | Files scanned | Contributor |
| A | BSD library | 50 | Joerg Jenderek |
| A | Binding of Isaac Rebirth packed Archive | 11 | |
| A | Go package (Win-64) (v1.x) | 401 | |
| A/B/C | Gordi's Math Attack data | 3 | |
| A | PA-RISC relocatable library | 20 | Joerg Jenderek |
| A | STK Attitude format | 5 | |
| A | System V 64-bit library | 15 | Joerg Jenderek |
| A00/A01/B01 | microTOOL install package | 28 | |
| A000/A001/A002 | NewTom NNT dental image/data | 177 | |
| A01/ARV | Eschalon Setup ARCV compressed container | 66 | |
| A01 | Invision delta Animation | 2 | |
| A01/FLX | Origin Systems's setup Archive | 10 | |
| A1WISH | Audials One Wishlist | 5 | |
| A2B | Adlib Tracker II instrument Bank | 2 | |
| A2B | DigitalPhono A2B Player Playlist | 4 | |
| A2D | Agros2D document | 11 | |
| A2F | Adlib Tracker II instrument (with fm-registers macro) | 2 | |
| A2I | Adlib Tracker II Instrument | 2 | |
| A2M | AdLib Tracker II Module | 174 | |
| A2M | Apple ][-Vision video | 8 | |
| A2MENU | Aston 2 Menu | 7 | |
| A2P | Adlib Tracker II Pattern | 2 | |
| A2R | A2R disk image (generic) | 4 | |
| A2R | A2R disk image (v1) | 2 | |
| A2R | A2R disk image (v2) | 2 | |
| A2R | A2R disk image (v3) | 5 | |
| A2T | Adlib Tracker II Tiny module | 2 | |
| A2THEME | Aston 2 Theme | 12 | |
| A2W | Adlib Tracker II instrument bank (with macro) | 2 | |
| A2W | Alice 2 World | 27 | |
| A3C | Alan v3 Compiled adventure | 8 | |
| A3D/X | Amapi 3D model | 38 | |
| A3D | AutoRENDER 3D model | 9 | |
| A3D | KOMPAS-3D Assemblies | 9 | |
| A3D | Model 3D (ASCII) | 4 | |
| A3P | Alice 3 Project | 8 | |
| A3P | GenCAM object model | 3 | |
| A3W | Unpackaged Authorware 3 for Windows data | 8 | |
| A3X | AutoIt v3 compiled script | 8 | |
| A4E/A5E/A6E | Authorware Packaged library | 15 | |
| A4L/A5L/A6L | Authorware Library | 7 | |
| A4P/A5P/A6P | Authorware Packaged file (w/o runtime) | 19 | |
| A4R/A5R/A6R | Authorware Packaged file (with runtime) | 14 | |
| A4W | Apple II Oasis for Windows savestate | 3 | |
| A5WCMP | Alpha Five Web Components | 18 | |
| A78 | Atari 7800 ROM | 10 | |
| A8K | Atari800Win Plus Keyboard | 3 | |
| A8S | Atari800Win Plus Snapshot (un-gzipped) | 4 | |
| A8T | Atari800Win Plus Trainer | 24 | |
| AA | Audible Audio | 12 | |
| AA | Audible Audio (oldest format) | 11 | |
| AA3 | ATRAC3 encoded audio | 5 | |
| AAB | Android App Bundle | 12 | |
| AAC | Astrid/Quartex AAC encoded audio | 6 | |
| AAC | MPEG-2 LC-AAC Audio | 6 | |
| AAC | MPEG-4 LC-AAC Audio | 3 | |
| AAE | Apple Sidecar data | 10 | |
| AAF | Advanced Authoring Format | 28 | |
| AAM | Art And Magic module | 4 | |
| AAM | Authorware Shocked File (Map) | 31 | |
| AAR | Aard Dictionary | 10 | |
| AAR | Android Archive | 5 | |
| AAR | Apple Archive (LZ4) | 2 | |
| AAR | Apple Archive (LZFSE) | 2 | |
| AAR | Apple Archive (LZMA) | 2 | |
| AAR | Apple Archive (generic) | 6 | Tyler Thorsted |
| AAR | Apple Archive (raw) | 2 | |
| AAR | Apple Archive (zlib) | 2 | |
| AARU/AARUF/AARUFORMAT/AIF | Aaru disk image | 4 | |
| AAS | Advanced Authoring System adventure | 10 | |
| AAS/AOS | Archos signed / encrypted data | 6 | |
| AASTORY | A-machine story | 3 | |
| AAUI | Acrobat User Interface data | 5 | |
| AAX | AAX compressed data | 6 | |
| AAX | Audible Enhanced Audio | 4 | |
| AB | AlphaBase data base (v2.x) | 7 | |
| AB | Android adb backup (unencrypted) | 14 | Markus Birth |
| AB1/FSA | ABIF - Applied Biosystems Inc. Format | 27 | |
| AB2I | AmiBlitz2 Image bitmap | 2 | |
| AB3 | PhotoImpact 3 Album | 15 | |
| AB3I | AmiBlitz3 Image bitmap | 3 | |
| ABA | Abacus spreadsheet | 3 | |
| ABA | Palm Address Book | 5 | |
| ABC | ABC FlowCharter document | 6 | |
| ABC | ABC notation | 2 | |
| ABC | ABC notation (old) | 6 | |
| ABC | Alembic Open Computer Graphics Exchange (HDF5) | 9 | |
| ABC | Alembic Open Computer Graphics Exchange (Ogawa) (v1.0) | 37 | |
| ABC | LEADTOOLS ABC bitmap | 5 | |
| ABCDP | Address Book CoreData Person | 6 | |
| ABD | ArtBase Design | 14 | |
| ABD | The Bat! Address Book | 17 | |
| ABE | ABE encoded data (original) | 18 | |
| ABEX | Enhanced Android Backup | 2 | |
| ABF | Altair Binary Format | 17 | |
| ABK | AMOS AMAL Bank | 2 | |
| ABK | AMOS Asm Bank | 2 | |
| ABK | AMOS Data Bank | 4 | |
| ABK | AMOS Icons Bank | 5 | |
| ABK | AMOS Memory Bank (generic) | 5 | |
| ABK | AMOS Menu Bank | 2 | |
| ABK | AMOS Music Bank | 20 | |
| ABK | AMOS Picture Bank | 4 | |
| ABK | AMOS Samples Bank | 2 | |
| ABK | AMOS Sprites Bank | 3 | |
| ABK | AMOS Work Bank | 2 | |
| ABK | Arena opening Book | 9 | |
| ABK | Need for Speed: Underground audio | 83 | Alvin Abdagic |
| ABL | Alpha Ball Level | 4 | |
| ABM | Arabesque Professional bitmapped drawing | 4 | |
| ABM | Audition music | 2 | |
| ABM | Deluxe Paint AnimBrush | 15 | |
| ABM | PhotoImpressions Album | 3 | |
| ABOX2 | Analog Box synth circuit | 97 | |
| ABP | ABComp compressed data (v2.x) | 3 | |
| ABS | AMOS Banks group | 10 | |
| ABS | Absolute Database file | 11 | |
| ABS | CUPL ABS | 6 | |
| ABS/BIN | Firmware with NCRC bootloader | 23 | |
| ABS | abs spreadsheet | 13 | |
| ABS | abs spreadsheet (with rem) | 10 | |
| ABT | Verity Collection Index About | 17 | |
| ABW | AbiWord document | 30 | |
| ABY | AOL Address Book | 14 | |
| AC/ACC | AC3D geometry/model | 78 | |
| AC/ACC | AC3D geometry/model (UTF-16 LE) | 4 | |
| AC/ACC | AC3D geometry/model (UTF-8) | 4 | |
| AC | Ancestral Quest family tree database (collaboration) | 2 | |
| AC1 | Agatha Christie: And Then There Were None save game | 45 | |
| AC1/AC2/ACB/ACRE/AC3/AC3SP/AC3MP/ACL/AC4/AC4SP/AC4MP/ACU/ACRO | Assassin's Creed game data container (generic) | 7 | |
| AC1D | AC1D-DC1A Packer | 7 | |
| AC2 | Agatha Christie: Murder on the Orient Express save game | 44 | |
| AC2 | Banana accounting data | 42 | |
| AC3 | Agatha Christie: Evil Under the Sun save game | 61 | |
| AC3 | Dolby Digital stream audio | 45 | Ryan Jones |
| ACB | Adobe Photoshop Color Book | 17 | |
| ACB/ACF/AWB | Atom Cue sheet Binary | 84 | Brian Pow |
| ACB | AutoCAD Color Book | 9 | |
| ACBM | IFF Amiga Contiguous BitMap | 2 | |
| ACC | Lotus Accessory | 21 | |
| ACC/RLT/SAM/SEQ/SPT/VOC | Philips Music Creator data (generic) | 75 | |
| ACCDB | Microsoft Access 2007 Database | 5 | |
| ACCDW | Microsoft Access Database Link | 4 | |
| ACCURIP | CUETools AccuRip log | 24 | |
| ACD | ACID Pro song | 8 | |
| ACD | ACID song | 90 | |
| ACD | Adobe Capture Document | 7 | Tyler Thorsted |
| ACD | Alan 2 Code | 15 | |
| ACD | RSLogix 5000 Program | 71 | |
| ACD | Sonic Foundry Acid music | 8 | |
| ACD-ZIP | ACID Pro project | 4 | |
| ACDB | Audio Calibration DataBase | 18 | |
| ACE | ACE compressed archive | 14 | |
| ACE | Jupiter Ace snapshot | 9 | |
| ACELIVE | Ace Stream Transport | 5 | |
| ACF | ASCII Color Format | 6 | |
| ACF | DB/TextWorks Database Access Control | 6 | |
| ACF | DreamLight PixelPalette colors data | 4 | |
| ACF | Microsoft Agent Character | 4 | |
| ACF | Steam Application manifest | 16 | |
| ACF | X-Plane Aircraft | 26 | |
| ACI | ACI development appraisal data | 8 | |
| ACIDCSA | Acid Cryptofiler encrypted data | 4 | |
| ACL | Office AutoCorrect List | 4 | |
| ACM | Interplay Compressed Audio Format | 45 | Kristopher Neidecker |
| ACM | Windows Audio Compression Manager driver | 54 | |
| ACMI | Tacview recording | 6 | |
| ACMI | Tacview recording (UTF-8 BOM) | 12 | |
| ACODE | AnkerMake printable package | 12 | |
| ACP/ACT/STA | Action! presentation (v2.5) | 6 | |
| ACP/ACT/STA | Action! presentation (v3.0) | 15 | |
| ACP | ArCon project | 4 | |
| ACP | EditPlus Auto Completion | 6 | |
| ACR | Adobe ACR sidecar mask data | 131 | Giulio Fornasar |
| ACR | American College of Radiology file | 6 | |
| ACS | Microsoft Agent Character | 14 | |
| ACS2 | AIMP Skin (v2) | 5 | |
| ACS3 | AIMP Skin (v3) | 6 | |
| ACS4 | AIMP Skin (v4) | 8 | |
| ACSM | Adobe Digital Editions Adobe Content Server Message | 4 | |
| ACT | ADPCM (?) compressed file recorded by some MP3 Players/Voice recorders | 6 | THE LoW |
| ACT | Astound Actor | 322 | |
| ACT | Cartooners Actor | 12 | |
| ACT | EA Seattle game data (UNC2) | 155 | |
| ACT | EA Seattle game data (UNCS) | 47 | |
| ACT | Microsoft Project 2.0-3.0 for DOS Activity | 3 | |
| ACT | Microsoft Project 4.0 for DOS Activity | 3 | |
| ACT | Playmation Action | 12 | |
| ACT | Train Simulator Activity | 8 | |
| ACTION/PROG | Conk Action/Program | 16 | |
| ACTION | Krita Action collection | 39 | |
| ACTIVEGSXML | ActiveGS PC configuration | 4 | |
| ACTIVEGSXML | ActiveGS iOS configuration | 4 | |
| ACX | Adobe Encore project media list | 8 | |
| AC_ | CaseWare 2005 Compressed file | 474 | Jim Grusendorf |
| AD | Anno Designer layout | 11 | |
| AD | Mac AppleDouble encoded | 5 | |
| AD1/E01/S01 | AccessData Encrypted disk image | 11 | |
| AD1 | AccessData Segmented image | 2 | |
| ADA | ADA MD5 | 15 | |
| ADA | Advanced Digital Audio lossless compressed audio | 23 | |
| ADB | CorelCENTRAL Address Book | 2 | |
| ADB/NDB/GDB/PDB | HP Phone/Database/Note database | 7 | |
| ADC | Adaptive Differential Coding audio | 2 | |
| ADC | XemiComputers Active Desktop Calendar | 8 | Ryan Jones |
| ADCP | Adobe Device Central Project | 4 | |
| ADD | AdLib music | 8 | |
| ADD | After Dark for DOS module | 33 | |
| ADF | ABackup backup disk image | 5 | |
| ADF | ARIS Document File | 19 | |
| ADF | Acorn Disc Filing System disk image (Map E) | 20 | |
| ADF/ADFS/ADL | Acorn Disc Filing System disk image (Map S) | 18 | |
| ADF | Actual Drawing project | 38 | Tyler Thorsted |
| ADF | Ad Designer project | 115 | |
| ADF | Advanced Data Format data base | 38 | |
| ADF | Ami-Back backup disk image | 4 | |
| ADF | Amiga Disk image File (FFS) | 3 | |
| ADF | Amiga Disk image File (FFS+DIRC) | 3 | |
| ADF | Amiga Disk image File (FFS+INTL) | 3 | |
| ADF | Amiga Disk image File (FFS+INTL+DIRC) | 3 | |
| ADF | Amiga Disk image File (OFS) | 3 | |
| ADF | Amiga Disk image File (OFS+DIRC) | 3 | |
| ADF | Amiga Disk image File (OFS+INTL) | 3 | |
| ADF | Amiga Disk image File (OFS+INTL+DIRC) | 3 | |
| ADF | Amiga Disk image File (generic) | 13 | Wayne Hardman |
| ADF | Amiga Kickstart disk image | 15 | |
| ADF | Antenna Data File | 75 | |
| ADF | EXT1 Extended Amiga Disk image File | 2 | |
| ADF | EXT2 Extended Amiga Disk image File | 3 | |
| ADF | PS/2 MicroChannel Adapter Description File | 29 | |
| ADF | PS/2 MicroChannel Adapter Description File (with CRLF) | 17 | |
| ADF | PS/2 MicroChannel Adapter Description File (with rem) | 19 | |
| ADF | Robot Arena hazard configuration | 7 | |
| ADF | Rohde-Schwarz M3TR bootloader | 2 | |
| ADF | Rohde-Schwarz M3TR data (generic) | 4 | |
| ADF | Rohde-Schwarz M3TR radio firmware | 2 | |
| ADF | SNAP Archive Data File | 3 | |
| ADF | SuperDOS Adapter File | 2 | |
| ADF | Xpress Tree disk | 3 | |
| ADF | Xpress backup disk (#1) | 3 | |
| ADI/ADIF | Amateur Data Interchange Format | 13 | |
| ADK | AngryDuck encrypted (ransomware) | 4 | |
| ADL | Micro-Channel Architecture Adapter Description Library | 3 | |
| ADL | openEHR Archetype Definition Language | 6 | |
| ADLIB | Martin Fernandez Ad Lib module | 7 | |
| ADM | Addict compiled dictionary | 15 | |
| ADM | Windows Policy Administrative Template | 13 | |
| ADM | Windows Policy Administrative Template (Unicode) | 58 | |
| ADM | Windows Policy Administrative Template (with rem) | 11 | |
| ADML | Group Policy Language-Specific Administrative Template | 35 | |
| ADML | Group Policy Language-Specific Administrative Template (UTF-16 LE) | 107 | |
| ADMX | Group Policy Administrative Template | 41 | |
| ADMX | Group Policy Administrative Template (UTF-16 LE) | 43 | |
| ADMX | Group Policy Administrative Template (UTF-8) | 184 | |
| ADN | Lotus 1-2-3 Add-In Application | 14 | |
| ADO | Adobe Duotone Options | 26 | |
| ADO | Adorage Animation | 3 | |
| ADP | Archimedes Protected Disk image (unzipped) | 5 | |
| ADP | Microsoft Access Project | 26 | |
| ADP | Qt Assistant Documentation Profile | 6 | |
| ADP | Xilam DERF audio | 94 | |
| ADR | Opera Hotlist (v2.0) / bookmark | 5 | |
| ADR | Smart Address address book (v1) | 3 | |
| ADR | Smart Address address book (v3) | 2 | |
| ADS | TunerPro DataStream definition | 16 | |
| ADSKLIB | Autodesk material Library | 25 | |
| ADT | Addict Thesaurus | 3 | |
| ADT | Advantage Data Server table | 4 | |
| ADT | Casio Pocket Viewer Add-in Data file | 3 | |
| ADU | Addict User Dictionary | 2 | |
| ADV | Advantage spreadsheet | 26 | |
| ADV/PCF | Gold Disk Office Calc/Graph spreadsheet | 78 | |
| ADV | Miles Sound System real mode drivers | 19 | |
| ADV | WordPerfect dictionary advise | 14 | Joerg Jenderek |
| ADX | ADX lossy compressed audio | 12 | |
| ADX | Aodix project | 3 | |
| ADX | Lotus Approach Database index | 9 | |
| ADX | MSX sound performance system Player XPL-A song | 73 | |
| ADX | TunerPro datastream definition format | 17 | |
| AD_ASM | Alibre Design Assembly | 57 | |
| AD_DRW | Alibre Design Drawing | 25 | |
| AD_PRT | Alibre Design Part | 231 | |
| AEA | ATRAC1 encoded audio | 8 | |
| AEA | Apple Encrypted Archive | 3 | |
| AEB | Adobe Edge Animate Binary | 4 | |
| AEDTHEME | Ashampoo Burning Studio Autorun Editor Theme | 24 | Joerg Jenderek |
| AEF | CA Visual Objects Application Export File (v1.x) | 17 | |
| AEF | Cisco Unity Express script | 16 | |
| AEGRAPHIC | Adobe After Effects Graphics | 22 | |
| AEH | iPer Advanced Embedded Hypertext | 24 | |
| AEI | Abyss Engine Image format | 2 | |
| AEM | STK Azimuth-Elevation Mask format | 6 | |
| AEP | After Effects Project | 42 | |
| AEP | ArcExplorer Project | 14 | |
| AEPX | After Effects Project XML | 16 | |
| AERO | Aero Studio song | 17 | |
| AES | AES Crypt encrypted | 3 | |
| AEX | AGES Game Script (v2.50) | 4 | |
| AF | Affinity document | 12 | |
| AF | MVP Paint Animation Format | 3 | |
| AF | SerenityOS Application File format | 63 | |
| AF3 | ABC FlowCharter chart | 20 | |
| AF3 | ABC FlowCharter chart (protected) | 2 | |
| AF4 | Artline Font | 35 | |
| AFA | Astrotite compressed archive | 3 | |
| AFB | AYFX Editor Bank | 4 | |
| AFD | AnFX Project | 31 | |
| AFDESIGN | Affinity Design document | 30 | |
| AFF | AGEMA File Format | 2 | |
| AFF | Advanced Forensic Format image | 5 | |
| AFF4 | Advanced Forensic Format 4 disk image | 24 | |
| AFI | Advanced Floppy Image | 4 | |
| AFL | Allways Font Library | 4 | |
| AFL | X-Plane Airfoils | 52 | |
| AFM | Adobe/Outline Font Metric | 1336 | |
| AFM | Adobe/Outline Font Metric (Fontographer) (MacBinary) | 8 | Joerg Jenderek |
| AFM | Hitachi AFM data | 4 | |
| AFM | Quesant AFM data | 2 | |
| AFN | ArtCAM Font | 84 | |
| AFOX | AmigaFox layout | 5 | |
| AFP | ABC FlowCharter shapes Palette | 25 | |
| AFPHOTO | Affinity Photo document | 20 | |
| AFPK | audfprint peak | 4 | |
| AFPT | audfprint hash | 4 | |
| AFR | Caneco BT project | 16 | |
| AFS/AFS_ARCHIVE | AFS game data archive | 2 | |
| AFS | AktivFilter project | 6 | |
| AFT | ABC FlowCharter Template | 5 | |
| AFW | ABC FlowCharter Workspace | 6 | |
| AFX | AFX compressed data | 4 | |
| AFX | AnFX Java Movie | 34 | |
| AFX | Auto FX PhotoGraphic Edges image | 50 | |
| AF~LOCK~ | Affinity Lock | 6 | |
| AG | Applixware Graphic | 9 | |
| AG | Lotus Agenda data objects (v2.0) | 20 | |
| AGA | Lotus Agenda data objects (v1.0) | 15 | |
| AGG | Dangerous Waters game data archive | 2 | |
| AGI | Sierra AGI music format | 14 | |
| AGN | AUTOMGEN project | 15 | |
| AGN | Psion S3a/3c/Siena Agenda | 2 | |
| AGR | Grace project file | 10 | |
| AGS | Atari Graphics Studio bitmap | 3 | |
| AGTEMPLATE | Adobe Photoshop Lightroom template | 6 | |
| AGX | Adventure Game eXecutable | 6 | |
| AHF | ASCII Header Format bitmap | 2 | |
| AHK | Autohotkey script (v2.x) | 3 | |
| AHN | Ahnenblatt genealogy data | 11 | |
| AHX | Abyss' Highest eXperience module (v1) | 21 | |
| AHX | Abyss' Highest eXperience module (v2) | 15 | |
| AI | Adobe Illustrator graphics | 123 | |
| AI | Adobe Illustrator graphics (exported by sK1) | 6 | |
| AI | Ai Archivator compressed archive | 12 | |
| AIA | Adobe Illustrator Action | 28 | |
| AIA | App Inventor for Android project | 12 | |
| AIC | Advanced Image Coding bitmap | 6 | |
| AIDOC | Allgeier Inovar Document | 4 | |
| AIDOCDEF | Allgeier Inovar Document Definition | 8 | |
| AIF/AIFF/AFF | AIFF Audio Interchange File Format | 30 | James Heinrich |
| AIF | AlterImage Font | 26 | |
| AIF | EPOC/Symbian Application Info | 26 | |
| AIF | OP-1 drum patch | 34 | |
| AIFC | AIFF-C (Audio Interchange File Format Compressed) | 3 | |
| AIG | Abracadata drawing | 2 | |
| AIK | Psion serie 3 AICA Sound Compressor audio | 3 | |
| AIML | Artificial Intelligence Markup Language | 93 | |
| AIMPPL | AIMP PlayList | 5 | |
| AIN | AIN compressed archive | 3 | |
| AIN | Source Engine Compiled AI Nodegraph | 156 | |
| AIP | Actual Installer Project | 7 | |
| AIP | Advanced Installer Project | 13 | Paul Beesley |
| AIPD/APD | AIPD bitmap | 11 | |
| AIR | Adobe Apollo Rich Internet Application (obsolete) | 22 | |
| AIR | Adobe Integrated Runtime | 15 | |
| AIR | Advanced Input Recording | 2 | |
| AIRPORTS | RealFlight Radio Control Flying Site - Airport | 2 | |
| AIU | Advanced Installer Updates configuration | 5 | |
| AIX | Adobe Illustrator Exchange | 4 | |
| AJP | Anfy Applet Generator Saved file | 20 | |
| AK | TracerCAD File (generic) | 2 | |
| AKG | Arkos Generic Z80 binary song | 5 | |
| AKI | Arkos Tracker Instrument | 118 | |
| AKM | Aksharamala Keymap Binary | 87 | Srinivas Annam |
| AKP | Akai AKP format | 4 | |
| AKPIC | AnkerMaker AI detection info | 12 | |
| AKS | AkAbak Script | 37 | |
| AKS | Arkos Tracker Song | 9 | |
| AKS | Arkos Tracker Song (zipped) | 7 | |
| AKT | AKT compressed archive (generic) | 6 | |
| AL3D | Alicona 3D image | 3 | |
| ALB | PowerAlbum Album (v1.x) | 5 | |
| ALB | PowerAlbum Album (v2.x) | 2 | |
| ALB | Roland Easy Juke 2 Album | 8 | |
| ALB | SJGPlay Album info | 27 | |
| ALB | Seattle FilmWorks / PhotoWorks photo album | 77 | Richard H. Jones |
| ALB | VCOM Web Easy album | 19 | |
| ALBM | HP Photosmart Photo Printing Album | 36 | |
| ALC/VLC | AcuCorp AcuCOBOL license | 7 | |
| ALE | Avid Log Exchange | 10 | |
| ALF | Afterlife saved game | 6 | |
| ALF | Alf test | 26 | |
| ALF | CPS Allegro Arrangement Library | 7 | |
| ALF | MSX Font | 114 | |
| ALF | W32Dasm Asm List File / project | 16 | |
| ALG | AlgoBox Algorithm | 28 | |
| ALG | CPS Allegro song | 7 | |
| ALGOBUILD | AlgoBuild project (v1.00) | 3 | |
| ALI | GNAT Ada Library Information | 99 | |
| ALIAS | Find and Run Robot (FARR) alias | 19 | |
| ALL/CHA/DAT/MAP/MDI/VGA | Amberstar game data | 17 | |
| ALL | Cubase song | 54 | |
| ALL | WordPerfect Printer info | 4 | |
| ALL | WordPerfect printer data | 7 | Joerg Jenderek |
| ALM | Aley's Module v1.0 | 4 | |
| ALM | Aley's Module v1.1-1.2 | 3 | |
| ALN | Clustal Alignment format | 15 | |
| ALP | AnyLogic Project | 31 | |
| ALS | Calmira Alias | 3 | |
| ALS | MPEG-4 ALS (Audio Lossless coding Standard) | 13 | |
| ALS | Psion serie 3 Application Alias | 2 | |
| ALTSTATE | Altirra save state | 3 | |
| ALX | BlackBerry Application Loader | 28 | |
| ALX1 | RASAero document | 28 | |
| ALZ | ALZip compressed archive | 8 | |
| AM | Ace Tracker module | 9 | |
| AM | AmiraMesh (ASCII) | 9 | |
| AM | AmiraMesh (binary) | 10 | |
| AM | Anark Media data | 4 | |
| AMAD | AY Amadeus chiptune | 7 | |
| AMB | Ambios AMB | 5 | |
| AMB | Amoeba Data (v1.x) | 12 | |
| AMB | Ancient Machines Book hypertext archive | 5 | |
| AMB | Modular V preset | 15 | |
| AMC | A.M.Composer 1.2 music | 10 | |
| AMC | Anark Media Component | 4 | |
| AMD | Amusic tracker (packed) song/module | 120 | |
| AMD | Animecha Animation Data | 3 | |
| AMF | Additive Manufacturing Format | 16 | |
| AMF | Advanced Module Format | 4 | |
| AMF/AMFF | Amiga Meta File Format | 2 | |
| AMF | Asylum Music Format module | 2 | |
| AMF | L3DT Attributes Map File | 3 | |
| AMG | AMGC compressed archive | 7 | |
| AMGP | AntiMicro Profile | 32 | |
| AMI | Apex Media Icon (bpp) | 45 | |
| AMI | Apex Media Icon (wpp) | 2 | |
| AMK | Automatic Mouse and Keyboard script | 9 | |
| AML | ACPI Machine Language (v1) | 6 | Joerg Jenderek |
| AML | ACPI Machine Language (v2) | 2 | Joerg Jenderek |
| AML | Abstract Markup Language | 8 | |
| AML | Microsoft Assistance Markup Language | 19 | |
| AML | Microsoft Assistance Markup Language (UTF-8) | 22 | |
| AML | Morpheus layout - project | 2 | |
| AMM | Amiga Money accounts (v1) | 3 | |
| AMM | Amiga Money books (v1) | 2 | |
| AMM | Amiga Money budgets (v1) | 2 | |
| AMM | Amiga Money categories (v1) | 2 | |
| AMM | Amiga Money credit (v1) | 2 | |
| AMM | Amiga Money data (v0) (generic) | 4 | |
| AMM | Amiga Money data (v1) (generic) | 25 | |
| AMM | Amiga Money data (v2) (generic) | 2 | |
| AMM | Amiga Money groups (v1) | 2 | |
| AMM | Amiga Money reports (v1) | 2 | |
| AMOD | AMOD format module | 2 | |
| AMOS | AMOS Pro source (generic) | 7 | |
| AMOS | AMOS Pro source (v1.00) | 2 | |
| AMOS | AMOS Pro source (v1.01) | 6 | |
| AMOS | AMOS Pro source (v1.11) | 3 | |
| AMOS | AMOS source (generic) | 12 | |
| AMOS | AMOS source (v1.00) | 7 | |
| AMOS | AMOS source (v1.23) | 25 | |
| AMOS | AMOS source (v1.3) | 5 | |
| AMOS | AMOS source (v1.34 Alt) | 10 | |
| AMOS | AMOS source (v1.34) | 24 | |
| AMPLXEPROJ | Intel VTune Amplifier XE Project | 8 | |
| AMR | AMR (Adaptive Multi Rate) encoded audio | 15 | |
| AMS | Extreme's Tracker module | 3 | |
| AMS | Velvet Studio Advanced Module System module | 11 | |
| AMT | ABBYY Finereader language data | 6 | |
| AMT | ArtMoney Table File | 444 | .Cryorb |
| AMU | ANMA RED music data | 79 | |
| AMU | Sony PictureGear Studio PhotoAlbum document | 7 | |
| AMV | MTV Movie | 9 | |
| AMW | Anark Media Workspace | 8 | |
| AMX | AND XSynth module | 2 | |
| AMX | Pawn compiled program | 26 | |
| AMXD | Ableton Max Patch | 15 | |
| AMXX | AMX Mod X plugin | 10 | |
| AN2 | AceNotes PIM data | 3 | |
| AN2 | S2 Engine Animation | 32 | |
| AN8 | Anim8or project | 20 | |
| AN8 | Anim8or project (with rem) | 4 | |
| ANA | Analysis for Windows structure | 4 | |
| ANB | Project Dogwaffle Animated Brush | 9 | |
| ANBM | IFF ANimated BitMap | 3 | |
| ANBR/ANMB | AnimBrush | 78 | |
| ANC | Motion Analysis Corp. ANC format | 6 | |
| ANE | Adobe AIR Native Extension | 14 | |
| ANI | Animation Magic video/Animation (v1) | 32 | |
| ANI | Animation Magic video/Animation (v2) | 3 | |
| ANI | Atari NEOchrome animation | 4 | |
| ANI | Atomic Bomberman Animation | 95 | |
| ANI | DK Multimedia Animation (22kHz audio) | 239 | |
| ANI | Eternity Engine Animation | 2 | |
| ANI | Imperium Galactica Animation | 462 | |
| ANI/CRX/LS | Links LS game data archive | 3 | |
| ANI | MP Entertainment SVGA Animation | 80 | |
| ANI | MST Quintus Animation | 2 | |
| ANI | PC Animate Plus Animation | 4 | |
| ANI | PC-Animation video | 33 | |
| ANI | Philips Video Graphics Animation | 3 | |
| ANI | Reunion Animation | 98 | |
| ANI | Talisman game Animation | 12 | |
| ANI | Windows Animated Cursor | 34 | |
| ANIM/ANM | IFF ANIM (Amiga delta/RLE encoded bitmap animation) | 36 | Wayne Hardman |
| ANIM | My Little Pony Magic Princess / Ice Age Animation | 517 | ego-lay_atman-bay |
| ANIM | Unity Animation | 17 | |
| ANIM | Voxlap Animation | 5 | |
| ANJUTA | Anjuta IDE project | 4 | |
| ANK | Children of the Nile city | 19 | |
| ANL | SimLife Animal | 67 | Kristopher Neidecker |
| ANL | WinAsks Editor Analysis (v2.00) | 2 | |
| ANM/ATZ | ASCARON Entertainment Animation | 125 | |
| ANM | DeluxePaint Animation | 20 | |
| ANM | League Of Legends bones based Animation | 5 | |
| ANM | MP Entertainment Animation | 91 | |
| ANM | Maeldemo Animation | 9 | |
| ANM | Ravenloft Animation | 13 | |
| ANM | Savage Warriors Animation | 4 | |
| ANM2 | The Binding of Isaac: Rebirth animation | 59 | |
| ANME | Anime Studio document | 110 | |
| ANN | Piklib 5 Animation data | 86 | |
| ANN | Piklib 8 Animation data | 596 | |
| ANN | Windows Help Annotation | 25 | Joerg Jenderek |
| ANS/ASC | ANSI escape sequence text | 44 | |
| ANS | ANSYS model data | 6 | |
| ANT | SimAnt saved game (Amiga) | 3 | |
| ANTMPL | Adobe Edge Animate Template | 8 | |
| ANY | AnyRail model railroad layout | 38 | |
| ANZ | ENVI Annotations | 6 | |
| AO | DAISY Authorization Object | 6 | |
| AO2/HDAO2 | Dynamic Auto-Painter Object | 57 | Scrapie |
| AO3/HDAO3 | Dynamic Auto-Painter Object | 72 | |
| AOA/AOP/HDAOP | Dynamic Auto-Painter Animation/Painting preset | 64 | |
| AOB | Arabesque Professional vector drawing | 3 | |
| AOF | Artlantis Object File | 33 | |
| AOFF | DEC-WSE Object File Format (text) | 23 | |
| AOFF | DEC-WSE Object File Format (text, start with LF) | 48 | |
| AOI | Art Of Illusion 3D scene (ungzipped) | 22 | |
| AOM | Adobe Download Manager | 12 | |
| AON | Art Of Noise 4-channel module | 13 | |
| AON | Art Of Noise 8-channel module | 8 | |
| AOP | AOP data | 2 | |
| AOS | AOS File Format | 7 | |
| AP | ALICE: The Personal Pascal Program | 27 | |
| AP | ArmPack Archive File | 11 | .Cryorb |
| AP | ArtPro page layout | 14 | |
| AP | STK Sensor Pointing format | 4 | |
| AP11/AP12/AP13/AP14/AP15/AP16 | Siemens TIA project (v11-16) | 12 | |
| AP11/AP12/AP13/AP14/AP15/AP16 | Siemens TIA project (v11-16) (UTF-8) | 79 | |
| AP6 | Norton pcAnywhere Automated Procedures | 2 | |
| APA | ArcPad Applet | 7 | |
| APALBUM | Aperture Album | 12 | |
| APC | Allways Printer Cartridge data | 27 | |
| APC | Cryo Interactive APC audio | 10 | |
| APC | Oracle Audio Percussion | 3 | |
| APC | a-Pac lossless compressed audio | 32 | |
| APCDOC | Ashampoo Photo Commander Document | 9 | Jochen Straub |
| APD | ACT! Printer driver data (v1.0) | 4 | |
| APD | Aldus Printer Driver | 23 | |
| APD | Allways Printer Driver | 126 | |
| APD/APS | Better On-Line Solutions Printer Driver | 34 | |
| APDISK | OS X system data | 7 | |
| APE | APE compressed archive | 5 | |
| APE | Monkey's Audio | 53 | |
| APEX | AVM APEX sample studio sound bank | 4 | |
| APEXBACKUP | Android Apex Launcher Backup | 14 | Joerg Jenderek |
| APF | Allways Printer Fonts info | 29 | |
| APF | Async Professional Fax | 22 | |
| APF | Vector Unit game assets | 8 | |
| APFOLDER | Aperture Folder | 3 | |
| APG | ArcPad Graphics layer | 4 | |
| API | Adobe Acrobat Reader Plugin | 12 | |
| APJ | ARM Project Manager Project | 6 | |
| APJ/PX4/VRX | ArduPilot JSON firmware | 126 | |
| APK | Android Package | 1502 | Avinash Rana |
| APK | Oracle Audio drumkit | 2 | |
| APKG | Exported Anki Flashcard Deck | 4 | |
| APKM | APKMirror Bundle | 9 | |
| APL | ACDSee plugin | 36 | fenixproductions |
| APL | ArcPad Layer | 6 | |
| APL | Authorware Library | 2 | |
| APL | Extra! for Windows APL keymap | 4 | |
| APL | HALNOTE Application | 5 | |
| APL | Monkey's Audio Image Link file | 4 | |
| APL | PaintSpa Palette | 4 | |
| APL/APP | Team Developer / SQLWindows application (binary) | 20 | |
| APM | Aldus Placeable Metafile | 2 | |
| APM | ArcPad Map | 10 | |
| APM | AutoPlay Menu Builder data | 37 | fengdaolong |
| APMASTER | Aperture Master | 3 | |
| APN | APN Wallpaper | 25 | |
| APNG/PNG | Animated Portable Network Graphics | 19 | |
| APNX | Amazon Kindle Page Number index | 3 | |
| APP | Atari V4E GFA Basic v3.6 executable | 14 | |
| APP | Authorware Application | 17 | |
| APP | Branch Always Program Packer compressed Atari ST program | 15 | |
| APP | CA Visual Objects Application (v1.x) | 26 | |
| APP | Cybiko Application | 17 | |
| APP | EPOC/Symbian OPL Application | 25 | |
| APP | GEM Application (Intel) | 11 | |
| APP | Generated application MS Visual FoxPro 7 | 21 | Nicola Marangon |
| APP/V4E/000/030/040/060 | MiNT Application/executable | 25 | |
| APP | OrbWorks PocketC CE Application | 15 | |
| APP/DL | Ozone GUI executable code | 50 | |
| APP | PRO-NTO Application | 33 | |
| APP | PRO-WAM Application | 10 | |
| APP/IMG | PSION Application/Image executable | 6 | |
| APP | Psion Oval Application | 13 | |
| APP | Symbian Application | 5 | |
| APP | Timex Datalink WristApp config | 10 | |
| APP | Z88 App info | 7 | |
| APP | Z88 Compressed RAM Apps (OZ 5.0) | 13 | |
| APP | lEEt/OS Application | 14 | |
| APPCACHE/MANIFEST | HTML5 AppCache Manifest | 11 | |
| APPIMAGE | AppImage package | 82 | |
| APPLICATION | ClickOnce Deployment Manifest | 5 | |
| APPUP | Erlang Application Upgrade | 7 | |
| APPX | Microsoft Windows AppX package | 9 | |
| APPXBUNDLE | Windows 8.1 App Bundle | 18 | |
| APPXMANIFEST | Windows 8 Appx Package Manifest | 16 | |
| APPXMANIFEST | Windows 8 Appx Package Manifest (UTF-8) | 19 | |
| APR | Apadana Project | 43 | |
| APR | ArcView Project | 32 | |
| APR | Artemis Presents! document (v2.0) | 11 | |
| APR | Lotus Approach (generic) | 21 | |
| APR | Lotus Approach v3.0 | 17 | |
| APS | AProSys module | 7 | |
| APS | ArcPad Stylesheet | 5 | |
| APS/SUE | Sudden Strike 2 game data archive | 15 | |
| APS | Visual C++ binary resource | 6 | |
| APT | APTCL output data | 4 | |
| APT | Adaptive Prediction Tree (APT) encoded bitmap | 9 | |
| APT | Android PandaHome theme | 10 | |
| APT | Electronic Arts APT game data | 15 | |
| APT | Team Developer / SQLWindows application (text) | 36 | |
| APT/APP | Team Developer / SQLWindows application (text) (v2.0) | 6 | |
| APUF | Puffer Armored encrypted archive | 5 | |
| APV | API Viewer Database | 3 | voodooattack |
| APVERSION | Aperture Version info | 4 | |
| APW | Any Password data | 2 | |
| APWZ | Aspen Plus Compound Document | 52 | |
| APX | Ability Office PhotoPaint bitmap | 2 | |
| APX | ArcPad bookmarks | 4 | |
| APX | ArcPad configuration | 8 | |
| APX | ArcPad preferences | 2 | |
| APX | Borland C++ Appexpert database | 9 | |
| APXL | Apple Keynote Presentation data | 25 | |
| AQ | Ancestral Quest family tree database | 5 | |
| AQ1 | AptiQuiz quiz data | 2 | |
| AQC | Touch Detective game data archive | 2 | |
| AQM | AlpineQuest Map | 3 | |
| AQX | Aquarius+ machine language program executable | 8 | |
| AQZ | Ancestral Quest family tree database (zipped) | 3 | |
| AR | ACCAreader document | 9 | |
| AR | AIX Small indexed archive (AIX prior to v4.3) | 7 | |
| AR/CO/XE | Ashlar-Vellum 3D models (generic) | 3 | |
| AR | Big Mutha Truckers 2 game data Archive | 2 | |
| AR | FMail Area configuration | 4 | |
| AR | Midtown Madness 2 car data | 8 | |
| AR | Midtown Madness 2 game data archive | 2 | |
| AR | Midtown Madness game data archive | 2 | |
| AR | PR archiving tool archive | 2 | |
| AR/A/LBR/LIB | ar archive | 10 | |
| AR/A/LBR | ar archive (thin) | 3 | |
| AR4 | Annin Robotics AR4 program source | 17 | |
| AR7 | ar7 compressed archive | 5 | |
| ARB | ARB Fragment shader | 10 | |
| ARB | ARB Vertex shader | 4 | |
| ARC | ArcMac compressed archive | 4 | |
| ARC | BGI/Ethornell game engine data (v1.0) | 4 | |
| ARC | BGI/Ethornell game engine data (v2.0) | 3 | |
| ARC | Bandai Namco game data archive | 2 | |
| ARC | Devil May Cry 4 game data archive | 2 | |
| ARC | EZBIND archive | 3 | |
| ARC | FreeArc compressed archive | 7 | |
| ARC | Internet Archive ARC File Format | 22 | |
| ARC/ARI | KaGuYa Engine resource data | 2 | |
| ARC | Majiro Engine resource data (v1) | 2 | |
| ARC | Majiro Engine resource data (v2) | 2 | |
| ARC | Majiro Engine resource data (v3) | 3 | |
| ARC | Mii Maker data archive | 4 | |
| ARC/SZS/YAZ0 | Nintendo Yaz0 compressed data | 7 | |
| ARC | Oberon compressed archive | 10 | Romiras |
| ARC | Silent Hill: Origins game data archive | 2 | |
| ARC | Xexor disk image | 2 | |
| ARCH00 | F.E.A.R. game archive | 19 | |
| ARCHITECT | SQL Power Architect Project | 19 | |
| ARCHIVE | MongoDB Archive (mongodump --archive format) | 7 | |
| ARCHIVERS | VirusZ II Archivers info | 2 | |
| ARD | Alphacam Router Drawing | 6 | |
| ARD | ArtiosCAD Drawing | 5 | |
| ARD | Autoread format (v2.0) | 4 | |
| ARD | Tiny Aibo Room Description | 9 | |
| ARDOUR | Ardour session | 6 | |
| ARDUBOY | Arduboy game package | 4 | |
| ARE | Infinity Engine Area (v9.1) | 118 | Sam. |
| ARE | Infinity Engine area description (v1.0) | 2 | |
| AREN | Advanced Renamer method | 9 | |
| ARF | Active Tutor data | 6 | |
| ARF | Axon Raw Format bitmap (big endian) | 2 | |
| ARF | Axon Raw Format bitmap (little endian) | 2 | |
| ARF | The Apprentice: Los Angeles game data Archive | 2 | |
| ARF | Webex Advanced Recording Format | 9 | |
| ARFF | Attribute-Relation File Format | 16 | |
| ARGO | ArgoUML project | 3 | |
| ARH | Squash compressed archive | 5 | |
| ARI | ARRIRAW image | 15 | |
| ARIA | Aria Maestosa project | 6 | |
| ARJ | ARJ compressed archive | 60 | |
| ARJ | ARJ compressed archive (multi volume 0x14) | 21 | Joerg Jenderek |
| ARJ | ARJ compressed archive (standard) | 328 | Joerg Jenderek |
| ARJ | ARJZ compressed archive | 5 | |
| ARK | DS Squeeze archive | 4 | |
| ARK | DS Squeeze compressed archive | 8 | |
| ARK | Fold compressed archive | 10 | |
| ARK | QuArk compressed archive | 4 | |
| ARL | Aureal Aspen sound bank | 15 | |
| ARMODEL | Kudan AR Model | 13 | |
| ARN | CD Autorun Creator package | 2 | |
| ARN | Sysinternals Autoruns data | 12 | Peter Glasl |
| ARN | Sysinternals Autoruns data (v14) | 23 | Joerg Jenderek |
| ARP | Audition Play Data | 5 | |
| ARP | MIDI Arpeggiator Arpeggio | 5 | |
| ARPBANK | ARP2600V preset | 17 | |
| ARQ | ARQ archive | 4 | |
| ARS | Alfred Hitchcock presents The Final Cut save game | 43 | |
| ARS | Carmageddon Saved Game | 5 | |
| ARS | Casanova: The Duel of the Black Rose save game | 52 | |
| ARSC | Android Package Resource | 22 | |
| ART | AOL ART (Johnson-Grace compressed) bitmap | 9 | |
| ART | ArtCAM model | 69 | |
| ART | ArtCAM model (old version) | 9 | |
| ART | Bernina Artista | 30 | FILExt |
| ART | Crayola Art Studio graphic Art | 159 | |
| ART | Designworks Sample (v3.5) | 40 | |
| ART | Gerber artwork | 6 | |
| ART | Greenstreet Art drawing | 26 | Joerg Jenderek |
| ART | Greenstreet Art drawing (old) | 5 | |
| ART | LogoArt drawing | 37 | |
| ART | The Office Publisher graphics Art (v1.x) | 24 | |
| ARTASK | Remedy User Tool shortcut | 7 | |
| ARTBORDER | ArtBorder data | 7 | |
| ARV | ASetup Installer Archive | 3 | |
| ARW/SR2 | Sony digital camera RAW image | 31 | |
| ARX | ARX compressed archive | 6 | |
| ARX | Arriflex CODEX HDE video | 195 | |
| AS | Applix spreadsheet | 10 | |
| AS/ADSC | Audio Sculpture module | 7 | |
| AS | Mac AppleSingle encoded | 9 | |
| AS/ZC | Zip Chunker fragment | 35 | |
| AS2PROJ | FlashDevelop ActionScript 2 Project | 14 | |
| AS3PROJ | FlashDevelop ActionScript 3 Project | 16 | |
| ASA | ArcGIS ArcScene data | 6 | |
| ASAR | asar Electron Archive | 13 | |
| ASB | IXimager forensic image | 2 | |
| ASC | 16bit DOS COM COMT text converted (with text wrapper) | 11 | |
| ASC | 3D Studio ASCII format | 19 | |
| ASC/TXT | 3DX 3D model | 4 | |
| ASC | ASCII Encoded HP 48 Object | 7 | |
| ASC | Atlantis Word Processor SpellCheck settings | 4 | |
| ASC | BRL-CAD Geometry (ASCII) | 22 | |
| ASC | BRL-CAD Geometry (older) (ASCII) | 27 | |
| ASC | Cheetah subtitles | 5 | |
| ASC/TXT | ENVI ASCII Plot | 18 | |
| ASC | Esri grid (ASCII) | 19 | |
| ASC | Jigsaws Galore Pieces | 54 | |
| ASC | LTSpice Circuit Schematic | 12 | |
| ASC | PGP ASCII-Armor | 10 | |
| ASC/TXT | PGP clear text signed message | 6 | |
| ASC/PGP/TXT | PGP message | 9 | |
| ASC | PGP private key block | 7 | |
| ASC/AEXPK/PGP/PUB/TXT | PGP public key block | 10 | |
| ASC | PGP signature | 14 | |
| ASC | Publisher's Type Foundry font (ASCII, v5) | 4 | |
| ASC | Rigaku Smartlab Pole Figure raw format | 9 | |
| ASC/TXT | SPIP ASCII export SPM text | 14 | |
| ASC | Symantec QandA macro | 3 | |
| ASC | WITec exported text data | 2 | |
| ASC | Wyko OPD ASCII data | 4 | |
| ASC | attocube Systems 2D data (ASCII) | 7 | |
| ASC | saltpack detached signature (ASCII) | 6 | |
| ASC | saltpack encrypted message (ASCII) | 4 | |
| ASC | saltpack signed message (ASCII) | 3 | |
| ASCX | Microsoft ASP.NET Web User Control | 10 | Brendan Hayes |
| ASCX | Microsoft ASP.NET Web User Control (UTF) | 17 | Brendan Hayes |
| ASD | ASD Archiever compressed archive | 4 | |
| ASD | Ableton Warp Analysis | 197 | |
| ASD | AlgoSim Data | 6 | |
| ASD | Allways Screen Driver | 15 | |
| ASD | Astound Presentation document (OLE) | 14 | |
| ASD | Astound Presentation document (old) | 4 | |
| ASD | DataFrog SF2000 firmware | 7 | |
| ASDATABASE | Microsoft SQL Server Analysis Services project | 18 | |
| ASDF | Advanced Scientific Data Format | 12 | |
| ASE | 3D Studio Max ASCII Export | 15 | |
| ASE | 3D Studio Max ASCII Export (UTF16-BE) | 4 | |
| ASE | 3D Studio Max ASCII Export (UTF16-LE) | 4 | |
| ASE/ASEF | Adobe Swatch Exchange File | 4 | |
| ASE/ASEPRITE | Aseprite Animated sprite | 19 | |
| ASF | A-Sound AutoSound File (v2.01) | 24 | |
| ASF | Acclaim Skeleton File | 6 | |
| ASF | Advanced Streaming Format (generic) | 16 | |
| ASF | Allways Screen Font | 8 | |
| ASF | BRender ASF | 65 | |
| ASF/STR/DAT/SDT/WVE | Electronic Arts ASF video (generic) | 36 | |
| ASF/DTY/MON/SPH | Electronic Arts audio Container System | 995 | |
| ASF | FIFA 2004 audio file | 337 | Alvin Abdagic |
| ASH | ASH compressed data | 17 | Label |
| ASHLANG | Ashampoo products translation | 608 | Joerg Jenderek |
| ASHPRJ | Ashampoo Burning Studio project | 6 | Ryan Jones |
| ASIC | ASiC container (generic) | 15 | |
| ASICE/SCE | ASiC Extended container | 9 | |
| ASICS | ASiC Simple container | 4 | |
| ASIF | Apple IIgs Sampled Instrument File | 2 | |
| ASK | WinAsks Player compiled app (v2.00) | 9 | |
| ASK | askSam data base | 5 | |
| ASK | askSam for Windows data base (v1) | 44 | |
| ASK | askSam for Windows data base (v2-3) | 46 | |
| ASK | askSam for Windows data base (v4-7) | 7 | |
| ASL | Quest Adventure Script (generic) | 9 | |
| ASLX | Quest Adventure Script (UTF-8) (v5) | 15 | |
| ASLX | Quest Adventure Script (v5) | 4 | |
| ASM | Solid Edge Assembly document | 147 | |
| ASM | freeCAD assembly | 15 | |
| ASMDEF | Unity Assembly Definition | 22 | |
| ASN | Atlantis Word Processor Sound Scheme | 6 | |
| ASP | ASAP Presentation | 8 | |
| ASPX | Microsoft ASP.NET Web Form | 11 | Brendan Hayes |
| ASPX | Microsoft ASP.NET Web Form (UTF) | 13 | Brendan Hayes |
| ASQ | ASQ info snapshot (v1.x) | 6 | |
| ASR | Asura engine Resource data (strings) (v2) | 6 | |
| ASR | Asura engine Resource data (strings) (v5) | 3 | |
| ASR | Asura engine Resources package (generic) | 2 | |
| ASR | Asura engine Resources package (zip) | 2 | |
| ASR | Asura engine Resources package (zlib) | 2 | |
| ASS/SSA | SubStation Alpha Subtitle | 33 | |
| ASS | SubStation Alpha Subtitle (Unicode) | 31 | |
| ASSET | Unity YAML Scene | 21 | |
| ASSETS | Unity Assets | 35 | |
| AST | 'Need for Speed: Underground' soundtrack | 4 | |
| AST | AST Audio Stream | 5 | |
| AST | Actionamics Sound Tool module | 6 | |
| AST | All Sound Tracker module | 20 | |
| AST/VIV | BIG4 Electronic Arts game data archive | 2 | |
| AST | Wii sound data (ADPCM) | 2 | |
| AST | Wii sound data (PCM) | 2 | |
| ASVF | Asphyre Sphinx Archive File | 71 | |
| ASX | Advanced Stream Redirector | 13 | |
| ASY | LTSpice Symbol | 6 | |
| ASZ | Balabolka Skin | 47 | |
| AT3 | Arxel game data container | 5 | |
| ATA | Antenna project | 27 | |
| ATBX | ArcGIS Toolbox (new) | 8 | |
| ATC | Caddie Catalog | 7 | |
| ATC | Caddie Category Sets | 7 | |
| ATC | Caddie Tool Sets | 8 | |
| ATC | SimCity 4 Animated Texture Collections | 2 | |
| ATDF | ASCII Test Data Format | 3 | |
| ATE | Kelly Slater's Pro Surfer textures | 2 | |
| ATF | ATF Texture | 13 | |
| ATF | Axon Text File format | 12 | |
| ATF | Persuasion AutoTemplate Interchange File Format | 2 | |
| ATH | Alienware AlienFX Theme | 8 | |
| ATH | Athena document (v1.x) | 25 | |
| ATH | Athena document (v2.x) | 3 | |
| ATHTUNE | athtune script | 6 | |
| ATL | Aladdin 4D ATList | 3 | |
| ATL | Artlantis 3D scene (gen) | 6 | |
| ATL | Artlantis 3D scene (v5.0) | 4 | |
| ATM | TerraGen Light and Atmosphere | 20 | Chris Malady |
| ATM | Vue D'Esprit 4 Atmosphere Preset | 138 | Alex Paven |
| ATN | Photoshop Action | 30 | |
| ATOMSVC | Atom Service info | 4 | |
| ATP | Atari 8-bit Protected disk image | 4 | |
| ATP3 | Automise Project (v3) | 22 | |
| ATPZ/ATZ2/ATZ3 | Automise Project (compressed) (gen) | 23 | |
| ATR | Atari ATR disk image | 22 | |
| ATS | Spycraft: The Great Game Animation data | 12 | |
| ATSP | TSPLIB Asymmetric Traveling Salesman Problem data | 19 | |
| ATT | AVEVA E3D attributes dump (v1.0) | 4 | |
| ATT | Calamus ASCII Translation Table | 14 | |
| ATT/GEO/IQT | MapTrip data (generic) | 9 | |
| ATT | Playmation Attributes | 49 | |
| ATTACHMENT | 1Password Cloud Keychain | 3 | |
| ATTR | iPhoto image data | 87 | |
| ATW | Anytime Organizer for Windows data (v2) | 9 | |
| ATX | ANTEX Antenna Exchange Format | 35 | |
| ATX | Apple iOS Texture | 16 | |
| ATX | VAPI/ATX Atari 8-bit disk image | 5 | |
| AU | Audacity audio block | 370 | |
| AU | NeXT/Sun uLaw/AUdio format | 13 | James Heinrich |
| AUD/MSC/RES | DAZ Pack game data archive | 8 | |
| AUD | DirectMusic Audio Path | 150 | |
| AUD | INRS-Telecom audio (10KHz) | 5 | |
| AUD | INRS-Telecom audio (12KHz) | 5 | |
| AUD | INRS-Telecom audio (16KHz) | 5 | |
| AUD | INRS-Telecom audio (20KHz) | 5 | |
| AUD | INRS-Telecom audio (6.5KHz) | 5 | |
| AUD | INRS-Telecom audio (8KHz) | 4 | |
| AUD | WeChat Audio message (SILK codec) | 3 | |
| AUD | Westwood Studios audio | 5 | |
| AUDINFO | MaxPad Audio Information/settings | 3 | |
| AUF | Audacity Block File | 2 | |
| AUI | ArcSoft UI | 2 | |
| AUM | Adobe Update Manager data | 6 | |
| AUM | Adobe Update Manager data (UTF-8) | 4 | |
| AUP | Audacity Project | 13 | |
| AUP | EAX Preset | 4 | |
| AUP3 | Audacity 3 Project | 13 | |
| AUP3 | Audacity 3 Project backup | 5 | |
| AUP3-SHM | Audacity 3 temporary data | 4 | |
| AUP3-WAL | Audacity 3 temporary data | 4 | |
| AUR | AutoREALM Map | 6 | |
| AUS | AutoREALM Symbols | 5 | |
| AUTOMATICDESTINATIONS-MS | Windows 7 Jump List | 23 | |
| AUTOPLAY | AutoPlay Media Studio Project | 14 | Ryan Jones |
| AVA | AvaaBook e-book | 2 | |
| AVASTSOUNDS | Avast! Soundpack | 5 | |
| AVB | Avid Editor Bin | 65 | Daniel |
| AVB | Microsoft Chat Character | 32 | |
| AVC | Kaspersky Anti-virus data base | 142 | kif aka AC |
| AVF | AVF video | 3 | |
| AVF | Amiga Vision Flow | 5 | |
| AVI | Audio Video Interleave video | 129 | |
| AVIF | AV1 Image File Format bitmap | 420 | |
| AVIFS | AV1 Image File Format Sequence bitmap | 16 | |
| AVJ | AntiVir Job | 3 | |
| AVL | ArcView Legend | 24 | |
| AVL | Avira AntiVir Log status report | 186 | Joerg Jenderek |
| AVM | Tools Media Corp. Ambient light (binary) | 3 | |
| AVM | Tools Media Corp. Ambient light (text) | 17 | |
| AVP | AntiVir Profile | 7 | |
| AVP | SimCity 4 Animation View Position | 2 | |
| AVR | Audio Visual Research sample | 4 | |
| AVR | Avira AntiVir message | 6 | Joerg Jenderek |
| AVRO | Avro serialized data | 6 | |
| AVROLAYOUT | Avro Keyboard Layout | 6 | |
| AVROLAYOUT | Avro Keyboard Layout (UTF-8) | 8 | |
| AVROSKIN | Avro Keyboard Skin | 6 | |
| AVROSKIN | Avro Keyboard Skin (UTF-8) | 29 | |
| AVS | AVSS Video | 2 | |
| AVS | Argonaut Video Sequence video | 25 | |
| AVS | Winamp Advanced Visualization Studio File | 112 | .Cryorb |
| AVT | CLO-SET Avatar | 6 | |
| AVW | Analyze AVW image | 2 | |
| AVW | Analyze AVW volume | 2 | |
| AW | Microsoft Answer Wizard | 47 | |
| AWA | AnimationWorks Accelerated movie | 2 | |
| AWA | Astound Animation | 8 | |
| AWB | ADX2 HCA Audio | 4 | |
| AWB | Adaptive Multi-Rate Wideband ACELP codec | 2 | |
| AWD | Artweaver Document | 3 | |
| AWD | Away3D scene (v2.x) | 6 | |
| AWD | Microsoft At Work Fax document | 13 | |
| AWEBLIB | AWeb Library/module | 24 | |
| AWEBPLUGIN | AWeb Plugin | 7 | |
| AWL | AWL programming language (Var. 1) | 10 | |
| AWL | AWL programming language (Var. 2) | 10 | |
| AWL | Animation Works playList | 4 | |
| AWLIVE | Active WebCam live capture | 4 | |
| AWM | AllWebMenus project (v2.xx) | 6 | |
| AWM | AllWebMenus project (v3.xx) | 6 | |
| AWM | AllWebMenus project (v4.xx) | 32 | |
| AWM | Astound / Animation Works Movie | 28 | |
| AWP | WINDEV Active WEBDEV Page | 4 | |
| AWR | CAMtastic Aperture Wizard template | 30 | |
| AWS | Ability Office Spreadsheet | 15 | |
| AWS | AppleWin Saved State (v1) | 2 | |
| AWS | Ariane WorkSpace | 27 | |
| AWSES | Active WebCam Settings | 6 | |
| AWW | Ability Write document | 10 | |
| AX | DirectShow filter | 78 | |
| AXE | AutoRoute Export file | 13 | |
| AXE | PICAXE compiled code | 3 | |
| AXF | Appearance eXchange Format | 38 | |
| AXF/BIN/GXB | GP32 eXecutable Binary | 17 | |
| AXP | Avid / Pinnacle Studio Project | 10 | |
| AXP | CDBurnerXP Audio compilation | 4 | |
| AXR | Elcomsoft Password Recovery config | 2 | |
| AXS | AXS module | 37 | |
| AXT | ZenWorks snAPPshot ASCII Application Object Template | 7 | |
| AXX | AxCrypt encrypted (v1) | 8 | |
| AXX | AxCrypt encrypted (v2) | 26 | |
| AY/EMUL | AY chiptune | 732 | |
| AYL | Ay Emul play List | 5 | |
| AYM | Z80 music code with AY music | 27 | |
| AYS | Ay Emul Skin (v2.0) | 34 | |
| AYS | CS-80V preset | 9 | |
| AZA | QazaR compressed file | 3 | |
| AZF | AirZip FileSECURE format (print quality) | 3 | |
| AZS | AirZip FileSECURE format (original only) | 2 | |
| AZW | Amazon Kindle eBook | 23 | |
| AZW | Amazon Kindle eBook (with DRM) | 12 | |
| AZW1/TPZ | Kindle Topaz eBook | 4 | |
| AZW3 | Amazon Kindle KF8 eBook | 35 | |
| AZW3 | Amazon Kindle KF8 eBook (with DRM) | 31 | |
| AZX | ZX Audio | 2 | |
| AZZ | AZZ Cardfile card | 10 | |
| audio/x-mod | Fred Editor SoundTrack | 4 | |