| Extension | File Type | Files scanned | Contributor |
| L01 | Encase Logical Evidence | 4 | Diego Marson |
| L01 | Logical File eVidence disk image | 2 | |
| L2R | Lineage II Replay | 4 | |
| L2R | Lineage II data | 2 | |
| L3 | Hitachi Basic Master Level 3 game | 4 | |
| L30 | Bitmapped Signum!2 printer font (Laser/Inkjet) | 5 | |
| L3K | BML3MK5 recorded keys | 4 | |
| L3R | BML3MK5 snapshot | 3 | |
| L4D | CINEMA 4D Layout | 2 | |
| L4D | Maxon Cinema 4D Layout (rel.6) | 2 | |
| L5K | Logix Designer project import/export format | 7 | |
| L5K | Logix Designer project import/export format (UTF-8) | 12 | |
| L5X | Logix Designer project import/export format (XML) (UTF-8) | 4 | |
| L64 | 64LAN container | 15 | |
| L6T | Line 6 Tone | 9 | |
| L86 | CP/M-86 library | 14 | |
| LA | La Lossless Audio compressed (generic) | 66 | |
| LA | La Lossless Audio compressed (v0.2) | 13 | |
| LA | La Lossless Audio compressed (v0.3) | 53 | |
| LA | La Lossless Audio compressed (v0.4) | 53 | |
| LA | libtool library control info | 81 | Joerg Jenderek |
| LAA | LucasArts Ad Lib Audio module | 9 | |
| LAB | Bar-One Lite label | 12 | |
| LAB | LucasArts game data archive | 14 | |
| LAB | Turbiscan raw results | 11 | |
| LAD | Company Ladder diagram | 6 | |
| LAD | JuggleKrazy Ladder diagram | 7 | |
| LAM | LambChop fragment | 16 | |
| LAN/GIS | ERDAS Image bitmap (v7.x) | 4 | |
| LANG | GtkSourceView language definition | 23 | |
| LAS | ASPRS Lidar Data Exchange Format | 15 | |
| LAS | CWLS Log ASCII Standard | 34 | |
| LAS | CWLS Log ASCII Standard (with rem) | 9 | |
| LASX | LAS sidecar auxilliary data | 2 | |
| LAT | MicroLathe object | 8 | |
| LAUNCH | Eclipse Launch configuration | 30 | |
| LAV | DNA Sequence Alignment | 8 | |
| LAV | STE Limited Audio/Video (v2) | 4 | |
| LAX | LaunchAnywhere configuration | 17 | |
| LAY | Advanced Layouter project | 3 | |
| LAY | Applause Layout data | 18 | |
| LAY | MAME Layout | 10 | |
| LAY | Magnetic Scrolls Collection Layout | 3 | |
| LAY | PolyPlot Layer (v3.0) | 17 | |
| LAY | Sprint Layout Printed Circuit Design (v6.0) | 5 | Abacom |
| LAY | SuperKey keyboard Layout | 2 | |
| LAY | Tecplot Layout | 19 | |
| LAY6 | Sprint Layout 6 PCB Layout | 10 | |
| LAYOUT | Code::Blocks Workspace Layout | 9 | |
| LAYOUT | Free42 Layout / skin | 18 | |
| LAZ | ASPRS Lidar Data Exchange Format (compressed) | 24 | |
| LAZ | LiquidApps project | 6 | |
| LB | Low Bitrate Packer compressed audio | 7 | |
| LB6/LBX | CODESYS Library | 25 | |
| LBK | Jeppesen/Mentor FliteLog Log | 3 | |
| LBL | Detached PDS Label info (v3) | 435 | |
| LBL | MapWindow Labels | 8 | |
| LBL | ZebraDesigner project | 12 | |
| LBL | dBASE IV Label design | 16 | |
| LBO | dBASE compiled Label | 2 | |
| LBR | C64 LiBRary container | 2 | |
| LBR | EAGLE Library | 86 | |
| LBR | EAGLE Library (XML) | 49 | |
| LBR | LU library | 2 | |
| LBR | Micro Focus COBOL Library | 3 | |
| LBR | Micro Focus VS Cobol library | 7 | |
| LBR | MinerVGA sprites Library | 2 | |
| LBRN | LightBurn project | 6 | |
| LBS | Omnis Studio Library | 78 | |
| LBT | P-touch Editor Lite Label | 4 | |
| LBW | Laubwerk model | 4 | |
| LBX | P-touch Editor Label | 2 | |
| LBX | SimTex LBX game data container | 2 | |
| LBXLLS | Logos Libronix 3.0 data | 6 | |
| LC | Laser Compact compressed screen | 2 | |
| LCA | SimpleFormat Changeables Graphic | 36 | |
| LCD | Lucid 3-D spreadsheet (v1.x) | 7 | |
| LCD | Lucid 3-D spreadsheet (v2.x) | 4 | |
| LCF | LICEcap Format lossless video | 2 | |
| LCH | Footprint/IBM Works Chart data | 2 | |
| LCH | LabChirp sound (v1.0x) | 26 | Luke Villalobos |
| LCK | Paradox Lock | 3 | |
| LCR | LabChirp preset (v1.0x) | 34 | Luke Villalobos |
| LCR | PLBM Games game data | 48 | |
| LD | Polycom SoundPoint IP firmware | 36 | |
| LD2 | Lingoes Dictionary | 6 | |
| LDB | Footprint/IBM Works Data Filer DataBase | 3 | |
| LDB | RPG Maker 2000/2003 DataBase | 2 | |
| LDBS | LDBS disk image (-v0.2) | 2 | |
| LDBS | LDBS disk image (generic) | 13 | |
| LDBS | LDBS disk image (v0.3) | 9 | |
| LDBST | LDBS text format disk image | 2 | |
| LDBST | LDBS text format disk image (UTF-8) | 2 | |
| LDE | Footprint/IBM Works Data Filer Design | 5 | |
| LDEFS | Ghidra Language Definitions | 43 | |
| LDF | Footprint/IBM Works Data Filer Form | 5 | |
| LDF | Lattice Diamond Project | 16 | |
| LDF | LuraDocument Format bitmap | 21 | |
| LDF | Lynx Disk Format | 9 | |
| LDF | Microsoft SQL Server log (generic) | 17 | Andreas |
| LDIF | LDAP Data Interchange Format | 17 | |
| LDL | Actor Library Definition Language | 12 | |
| LDM | Ludek Maker bitmap | 2 | |
| LDP | Altium Designer Layer Pairs export data | 10 | |
| LDR | GoDot C64 Image Processing - Loader | 24 | |
| LDR | LDraw Model | 15 | |
| LDS | LD Linker Script | 10 | |
| LDS | LD Linker Script (with rem) | 10 | |
| LDS | Lingoes Dictionary | 3 | |
| LDS | Liquid Digitized Sample Specification | 2 | |
| LDS | Sentinel RMS generator license | 4 | |
| LDW | Little Draw Drawing | 5 | |
| LDW | Virtual Villagers data | 4 | |
| LDX | Lingoes Dictionary | 12 | fengdaolong |
| LDX | Liquid Executable bytecode | 142 | |
| LEF | LEN Exchange Format | 9 | |
| LEF | Lenex XML data | 8 | |
| LEGOBATMAN2SAVEGAMEDATA | LEGO Batman 2 Saved Game | 6 | |
| LEP | Lepton bitmap | 2 | |
| LEP | Lepton bitmap (zlib compressed) | 2 | |
| LES/CBT | Microsoft Lesson/tutorial | 8 | |
| LET | CharlieWrite document | 6 | |
| LEV | Assault Wing level | 15 | |
| LEV | Big Red Racing Level | 26 | |
| LEV | Crimson Fields Level data | 22 | |
| LEV | Levelogger Software Data | 9 | |
| LEV | Teenage Mutant Ninja Turtles Level data | 6 | |
| LEX | Polar SpellChecker dictionary | 13 | |
| LEX/THS | Proximity Technology Lexicon/Thesaurus | 12 | |
| LFD | Lucas Film Data - Panel | 7 | |
| LFD | LucasFilm Data - LucasArts game resource | 58 | |
| LFM | Lazarus Form | 13 | |
| LFP | Lytro Light Field Picture web format | 28 | |
| LFT | 3D Studio Loft Object | 35 | Tyler Thorsted |
| LFVIEW | Leapfrog Scene | 3 | |
| LG | ARHANGEL compressed archive | 4 | |
| LG | Leonard Guides compiled data | 2 | |
| LG32 | GFA-BASIC 32 library | 58 | |
| LGC/LGD | Windows application log | 3 | |
| LGD | Radix Level Game Design | 3 | Robert Winkens |
| LGF | Logomotion Graphic File | 3 | |
| LGL | Caligari TrueSpace Light Library | 16 | |
| LGO | Modern ListGeo Output | 94 | |
| LGO | Windows logo drawing code | 13 | |
| LGP | Final Fantasy Game Archive | 2 | |
| LGP | Logitech G15 keyboard Profile | 7 | |
| LGR | MiAmiga Ledger data | 5 | |
| LGS | Leica Geosystems universal digital reality project | 13 | Tyler Thorsted |
| LGX | Logistix spreadsheet | 14 | |
| LHA | Amiga WHDLoad package (lha compressed) | 19 | |
| LHTS | The Movies Editor Text String Database | 3 | |
| LHW | Lhwarp compressed disk image | 4 | |
| LIA | Avatar Studio Animation | 21 | |
| LIA | P-CAD ASCII Library | 2 | |
| LIB/OBJ | Amiga Hunk library/object code | 15 | |
| LIB | CIRCAD source library (v4.x) | 4 | |
| LIB | CIRCAD source library (v5.x) | 12 | |
| LIB | Central Point Software Library/overlay (v2) | 2 | |
| LIB | Central Point Software Library/overlay (v3) | 2 | |
| LIB | Chess Assistant Library | 6 | |
| LIB | DipTrace Pattern Library | 53 | |
| LIB | EEDraw Library | 16 | |
| LIB | Electronic Arts LIB container | 2 | |
| LIB | High Speed Pascal compiled Units Library | 5 | |
| LIB | KiCad part Library | 5 | |
| LIB | Maple V R4 Library | 2 | |
| LIB | Maple V R5 Library | 2 | |
| LIB | Maple V R6 Library | 2 | |
| LIB | MegaPaint symbols Library | 2 | |
| LIB | Microsoft Basic 7.x compiled library | 46 | |
| LIB | Microsoft Basic compiled library (generic) | 52 | |
| LIB | Microsoft VBDOS 1.00 compiled library | 26 | |
| LIB | Microsoft Visual C Library | 109 | |
| LIB | Mythos Software LIB game data container | 2 | |
| LIB | OrCAD Library model | 8 | |
| LIB | P-CAD binary Library | 912 | |
| LIB | TML BASIC Library | 26 | |
| LIB | The Office Publisher Library (v1.x) | 63 | |
| LIB | ULTIboard Library | 24 | |
| LIB | ULTIcap Library | 40 | |
| LIB4D | Cinema 4D Preset Library | 5 | |
| LIBPKG | Altium Designer integrated Library Package | 23 | |
| LIBPKG | Altium Designer integrated Library Package (UTF8) | 9 | |
| LIBR | Music-X patch Library | 4 | |
| LIBRARY-MS | Microsoft Windows library description | 5 | |
| LIBZIP | Camtasia Studio Zipped Library | 5 | |
| LIC | AKVIS License | 3 | |
| LIC | ESET NOD32 Antivirus License data | 9 | |
| LIC | MATLAB license passcode | 5 | |
| LIC | MathWorks License | 9 | |
| LIC | Menavrus License | 3 | |
| LIC | Veeam Backup and Replication License | 10 | |
| LID | InstallShield Language Identifier | 12 | |
| LID | Lextek Language Identification Module | 4 | |
| LID | Skunny Kart Library game data | 4 | |
| LIF/HPI | HP Logical Interchange Format disk image | 9 | Joerg Jenderek |
| LIF | LIF installer-archive format | 17 | |
| LIF | LIFE 3000 status | 8 | |
| LIF | Lego Digital Designer data | 5 | |
| LIF | Leica Image File Format | 14 | |
| LIF | Life cellular automata format | 6 | |
| LIFT | Lexicon Interchange FormaT | 19 | |
| LIGHT | Plotter3D Light | 7 | |
| LIGHTHOUSE-PROJECT | Lighthouse Project | 12 | |
| LIGHTS | Create+Shade Lights | 4 | |
| LIGT | Caligari TrueSpace Light (v2.x) | 5 | |
| LIM | Lernout and Hauspie data | 72 | |
| LIM | Limit compressed archive | 17 | |
| LIN/MAP | Electronic Arts interactive sequence | 3 | |
| LIN | X-Plane Painted Line | 7 | |
| LING | Linguae dictionary | 3 | |
| LIO | Avatar Studio LIO | 289 | |
| LION | Lionheart module | 10 | |
| LIQ | Liquid Tracker module | 6 | |
| LISAEM | LisaEm configuration | 2 | |
| LISPM | Lisp Machine bitmap | 2 | |
| LIST | JAR Index | 10 | |
| LIST | iPhone contacts List | 10 | |
| LIT | Fractal Design Painter Lighting Lib | 4 | |
| LIT | Microsoft Reader eBook | 515 | |
| LIT | Microsoft Reader eBook (no DRM) | 49 | |
| LIT | Quake colored light data | 11 | |
| LITEMOD | Minecraft LiteLoader Mod | 8 | |
| LITTLE | Mozilla startupCache | 12 | Joerg Jenderek |
| LIV | LiveMotion project | 27 | |
| LIZ | Lizard compressed data | 10 | |
| LI_ | Cornel Huth compressed library | 6 | |
| LK12 | Liko-12 disk | 6 | |
| LKD | Pioneer OEL screensaver | 13 | |
| LL | Combit List and Label printer setup file | 15 | |
| LLM | Linden binary Mesh | 7 | |
| LLMESH | Linden Lab Mesh | 340 | |
| LLSD | Linden Lab Structured Data | 6 | |
| LM | Windows LM data | 2 | |
| LMA | Learning Mobile Author (LMA) Project | 5 | |
| LMD | Sony PictureGear Studio PrintStudio template | 143 | |
| LME | Leggless Music Editor module | 7 | |
| LMF | Quartus Library Mapping File | 6 | |
| LMK | Sothink Logo Maker logo | 27 | |
| LMP | Opticks Lamp | 9 | |
| LMP | Sonic Robo Blast 2 replay/demo | 2 | |
| LMS | LEGO Mindstorms EV3 bytecode Language | 12 | |
| LMS | Lego Mindstorms Robot Inventor code | 10 | |
| LMS | Turbo Fractal Generator Lindenmayer-System | 9 | |
| LMT | RPG Maker 2000/2003 Map Tree | 2 | |
| LMU | RPG Maker 2000/2003 Map | 41 | |
| LMU | Sony PictureGear Studio PrintStudio document | 4 | |
| LMX | Lomax game data | 47 | |
| LMX | Route 66 Landmarks | 6 | |
| LN | Seal Link | 25 | |
| LNARC | LucaNet archive (v2.0) | 2 | |
| LND | 3D Landscape project (v1.0) | 8 | |
| LNF | Look and Feel screen | 3 | |
| LNG | Necromancer's Dos Navigator Language | 2 | |
| LNG | OpenTTD Language data | 56 | |
| LNG | SourceEdit Language Definition | 29 | |
| LNG | SvarDOS Language | 8 | |
| LNG | VirtualBus Language | 6 | |
| LNK | Windows Shortcut | 506 | |
| LNR | Lenen video | 6 | |
| LNX | Atari Lynx ROM | 23 | |
| LNX | Lynx archive | 23 | |
| LOADTEST | Visual Studio LoadTest project | 11 | |
| LOC | Dr. Halo IV Locator driver | 6 | |
| LOC | EA Localized Strings game data | 4 | |
| LOC | The Touryst game data | 2 | |
| LOC | Topografix's EasyGPS/TerraByte Location file | 13 | |
| LOCAL | Borland user specific project options | 7 | |
| LOCK | Cargo lock | 17 | |
| LOCK | Conda Lock | 17 | |
| LOCK | Ghidra project Lock | 6 | |
| LOCK | WiredTiger Lock | 3 | |
| LOCK | Yarn Lock | 9 | |
| LOD | Logitech Modula-2 Loadable program (v1.x) | 11 | |
| LOD | Logitech Modula-2 Loadable program (v2.x) | 10 | |
| LOD | SPI Flash 32 firmware | 16 | |
| LODS | DCS LODS info | 11 | |
| LOF | Leica Object Format | 16 | |
| LOG | AIBB results log | 3 | |
| LOG | AMIDiag diagnostic report | 2 | |
| LOG | BTSnoop capture format | 4 | |
| LOG | Cabrillo Log (v2.0) | 9 | |
| LOG | Cabrillo Log (v3.0) | 16 | |
| LOG | DxWnd Log | 15 | |
| LOG | HijackThis logfile | 3 | |
| LOG | Microsoft IIS log | 11 | |
| LOG | Nmap scan results | 10 | |
| LOG | OGW Log | 24 | |
| LOG | Siemens ORSI Log | 2 | |
| LOG/LOG1/LOG2 | Windows NT Registry Hive (transaction 1) | 4 | |
| LOG/LOG1/LOG2 | Windows NT Registry Hive (transaction 2) | 4 | |
| LOG/LOG1/LOG2 | Windows NT Registry Hive (transaction 6) | 4 | |
| LOG | Wise Installer log | 14 | |
| LOG | ddrescue mapfile/Logfile | 10 | |
| LOGBOOK3 | SportTracks Log | 9 | |
| LOGICX | Logic Pro X project | 5 | |
| LOGONVISTA | LogonStudio Vista logon image | 4 | |
| LOGONXP | LogonStudio theme | 9 | |
| LOGOS4 | Logos 4 data | 12 | |
| LOOK | SpeedGrade Look | 8 | |
| LOP | VideoMaxe Layout Preset | 4 | |
| LOT | InterBase Layout (v1.0) | 9 | |
| LP | LaTeX-CAD drawing | 16 | |
| LP | LibrePCB Project | 4 | |
| LP | LibrePCB board | 2 | |
| LP | LibrePCB board user settings | 2 | |
| LP | LibrePCB boards list | 2 | |
| LP | LibrePCB circuit | 2 | |
| LP | LibrePCB component | 14 | |
| LP | LibrePCB data (generic) | 2560 | |
| LP | LibrePCB electrical rule check | 2 | |
| LP | LibrePCB jobs list | 2 | |
| LP | LibrePCB project metadata | 2 | |
| LP | LibrePCB project settings | 2 | |
| LP | LibrePCB schematic | 2 | |
| LP | LibrePCB schematics list | 2 | |
| LP | LibrePCB symbol | 20 | |
| LP | Lightscape Preparatation | 6 | |
| LPAQ | lpaq compressed data (generic) | 15 | |
| LPAQ1 | lpaq1 compressed data | 2 | |
| LPATCH | Lame Patcher Patch | 10 | |
| LPD | Avery Label Pro label (v2-3.0) | 2 | |
| LPD | Lecturnity Player file | 22 | Meigel |
| LPI | Lazarus Project Information | 27 | |
| LPI | LivePix project (v2.5) | 203 | |
| LPK | Lazarus Package | 10 | |
| LPK | Tecplot Layout Package | 6 | |
| LPKG | Liferay Application | 6 | |
| LPMD | LPMD Molecular Data | 4 | |
| LPPZ | LibrePCB Project Zipped | 9 | |
| LPS | Lazarus Project Session | 8 | |
| LPU | Passolo Localization Project | 63 | fengdaolong |
| LQM/JLQM | LG QuickMemo note | 6 | |
| LQT | Liquid Audio | 4 | |
| LRC | Lerc2 bitmap | 2 | |
| LRC | Lyric file (with ID tags) | 8 | |
| LRCAT | Adobe Lightroom Catalog | 37 | |
| LRF | Lotus Raster Font | 61 | |
| LRF | Unencrypted BBeB - BroadBand eBook | 8 | |
| LRG | xRes multi-resolution bitmap | 19 | Tyler Thorsted |
| LRPREV | Lightroom preview data | 2337 | |
| LRS | Lexar Encrypted file | 3 | |
| LRTEMPLATE | Adobe Photoshop Lightroom Template | 88 | |
| LRZ | Long Range Zip compressed | 2 | |
| LS | Lightscape Radiosity | 5 | |
| LS3PROJ | Visual Studio LightSwitch (V3) Project | 6 | |
| LSA | Domino Designer Agent | 9 | |
| LSC | LOGO!Soft Comfort Circuit | 11 | |
| LSD | ABBYY Lingvo dictionary | 55 | kif aka AC |
| LSD | PointCab LSD binary pointcloud data | 38 | |
| LSDX | PointCab Scan Project Description | 4 | |
| LSE | PointCab project | 12 | |
| LSET | Worm Wars Levelset | 3 | |
| LSG | LimeSurvey Group structure | 3 | |
| LSIM | LogicSim circuit (Java ver.) | 6 | |
| LSL | LiveSplit Layout | 11 | |
| LSL | SuperMap World GIS Line Style Library | 6 | Kieran O'Donnell |
| LSM | Linux Software Map entry (gen) | 52 | |
| LSM | Linux Software Map entry (v2) | 19 | |
| LSM | Linux Software Map entry (v3) | 12 | |
| LSM | Linux Software Map entry (v4) | 21 | |
| LSM | Lotus Movie | 5 | |
| LSMV | Lsnes movie capture | 10 | |
| LSO | Logic Song (generic) | 99 | |
| LSO | Logic Song (v1) | 5 | |
| LSO | Logic Song (v2) | 4 | |
| LSO | Logic Song (v4) | 79 | |
| LSP | AutoCAD Protected LISP code | 2 | |
| LSPROJ | Visual Studio LightSwitch Project | 12 | |
| LSS | Footprint/IBM Works SpreadSheet | 4 | |
| LSS | Handy savestate (v2) | 2 | |
| LSS | Handy savestate (v3) | 12 | |
| LSS/16 | LSS16 SYSLINUX Splash image | 4 | |
| LSS | Legato SpreadSheet | 14 | |
| LSS | LimeSurvey Survey | 13 | |
| LSS | LiveSplit Split | 4 | |
| LSS | LiveSplit Split (UTF-8) | 8 | |
| LST | Adobe FontList | 9 | |
| LST | Brik checksums | 12 | |
| LST | CUPL error Listing | 6 | |
| LST | FailSafe Computer Guardian List | 2 | |
| LST | HyperACCESS hosts password List (v2) | 2 | |
| LST | IBM AntiVirus virus signatures | 5 | |
| LST | IMS music List | 2 | |
| LST | Kaspersky Lab black list file | 3 | |
| LST | Microsoft Setup Toolkit for Windows files List | 7 | |
| LST | SyncTERM dialing directory | 4 | |
| LSXPROJ | Visual Studio LightSwitch Project | 8 | |
| LSXTPROJ | Visual Studio LightSwitch project | 6 | |
| LSZ | Litestep theme | 8 | |
| LT | Student Writing Center Letter | 2 | |
| LT/JN/NL/RP/SG/LTT/NLT/RPT/SGT | Student Writing Center document (generic) | 23 | |
| LT2 | Poser Light set | 16 | |
| LTA | Lead Technologies compressed Archive | 3 | |
| LTD | LogTag Data | 2 | |
| LTF | Frogans Short-cut | 8 | |
| LTM | Lotus Forms Template | 3 | |
| LTN | LinkTreeNote document | 5 | |
| LTP | LTP Nuclear ZX tape image | 3 | |
| LTR | WinWay Letter (v4.0) | 10 | |
| LTW | Incredimail Letter creator project | 8 | |
| LUA | Ardour Lua plugin | 132 | |
| LUA | Ardour Lua plugin (with rem) | 7 | |
| LUACODEC | Reason Remote Lua Codec | 5 | |
| LUAR | UltraDefrag Lua Report | 3 | |
| LUT | Houdini LUT | 73 | |
| LUT | MSS LUT | 12 | |
| LUT | Olympus OIF LUT | 7 | |
| LVA | Logitech Video Effects Avatar | 6 | |
| LVDD | LabVIEW Data Dashboard | 15 | |
| LVF | Lightweight Video Format video | 5 | |
| LVF | Logitech Video Effects Face Accessory | 10 | |
| LVF | Logo Report View File | 2 | |
| LVF | Lotus Vector Font | 13 | |
| LVI | Lazesoft disk image | 5 | |
| LVL/SPE | Abuse Level | 157 | |
| LVL | Microtime Animal level data | 2 | |
| LVL | Star Wars Battlefront game data archive | 2 | |
| LVLIB | LabVIEW project Library | 5 | |
| LVLIB | LabVIEW project Library (UTF-8) | 10 | |
| LVLPS | LabVIEW Local Project Settings | 6 | |
| LVLX | PGE Extendable Level | 4 | |
| LVM | LabVIEW Measurement | 8 | |
| LVM | LiveSwif Movie (ungzipped) | 6 | |
| LVPROJ | LabVIEW Project | 14 | |
| LVW | Livewire Document | 8 | |
| LW | LiteWave compressed audio | 48 | |
| LWC/LWE/LWH/LWM | LinkWay data | 44 | |
| LWF | LuraWave Format bitmap | 27 | |
| LWG | Ludwig project | 13 | |
| LWI | LightWork Image bitmap | 7 | |
| LWO/LW/LIGHTWAVE | LightWave 3D Object | 79 | |
| LWP | Footprint/IBM Works Document | 19 | |
| LWP | IBM Works for OS/2 word processor document | 2 | |
| LWP | Lotus Word Pro document (generic) | 10 | |
| LWP | Lotus Word Pro document (v7) | 35 | |
| LWR | Logo Writer page (v2.0) | 85 | |
| LWS/SCN | LightWave 3D Scene | 224 | |
| LWTP | LimeWire theme | 13 | |
| LX01 | EnCase Lx01 Logical format | 3 | |
| LXF | LEGO Exchange Format - Digital Designer | 19 | |
| LXF | Leitch Native Stream Format video | 2 | |
| LXF | SPLASH - Lenex compressed data | 7 | |
| LXFML | LEGO Digital Designer XML data | 14 | |
| LXO | Luxology 3D scene | 4 | |
| LXT | interLaced eXtensible Trace (v1) | 0 | Joerg Jenderek |
| LXXPLOT | LXBeams Light Plot | 10 | |
| LY/ILY | LilyPond music score | 860 | |
| LY | Softdesk AdCADD layer default | 7 | |
| LYNXSNAPSHOT | Jynx Snapshot | 6 | |
| LYR | ArcGIS Layer | 44 | |
| LYR | ImageEn Layer | 4 | |
| LYR | Project Dogwaffle layered bitmap | 7 | |
| LYRX | ArcGIS Pro Layer | 14 | |
| LYS | Lychee Slicer Scene | 39 | |
| LYT | DESQview/X Layout | 3 | |
| LYT | Newton Toolkit Layout settings | 3 | |
| LYT | PCB Layout | 7 | |
| LYT | Prima PrintMagic Layout | 309 | |
| LYX | LyX document | 15 | |
| LYZ | LaserDRW drawing | 2 | |
| LZ | LZIP compressed archive | 6 | |
| LZ1 | LZBW1 compressed data | 3 | |
| LZ4 | LZ4 compressed stream | 2 | |
| LZ4 | LZ4 compressed stream (Mozilla) | 10 | Joerg Jenderek |
| LZ4 | LZ4 compressed stream (old) | 2 | |
| LZ4 | LZ4 compressed stream (v1) | 0 | Joerg Jenderek |
| LZ5 | LZ5 compressed stream | 4 | |
| LZA | LZA animation/video | 3 | |
| LZA | LZA compressed archive | 3 | |
| LZC | Need for Speed game data | 7 | |
| LZD | LDIFF Differences Data (v1.0) | 6 | |
| LZD | LDIFF Differences Data (v2.0) | 2 | |
| LZH/LHA | LHARC/LZARK compressed archive (generic) | 32 | |
| LZH | LHARK compressed archive | 5 | |
| LZH | X-Finder theme | 15 | |
| LZHAM | LZHAM compressed data | 3 | |
| LZMA | LZMA compressed archive | 70 | selepo |
| LZO | lzop compressed | 5 | |
| LZP | LazPaint bitmap | 2 | |
| LZRC | Sony PS3 LZRC compressed data | 4 | Masamune3210 |
| LZS | LArc compressed archive | 12 | |
| LZS | LZS/Stac compressed data | 2 | |
| LZS | SkyRoads bitmap | 17 | |
| LZT | LZGT compressed data | 5 | |
| LZT | LzTurbo compressed | 6 | |
| LZU | LZUF compressed data | 3 | |
| LZX | LZX Amiga compressed archive | 83 | Lukasz Jakubowski |
| LZZ | LZA compressed data | 4 | |
