| Extension | Information |
| N | Nuke Randomic Life Generator |
| N1 | Nuke Randomic Life Generator |
| N1E | OM2 OMALI NENA Encrypted Document Version 1 |
| N2E | OM2 OMALI NENA Encrypted Document Version 2 |
| N2P | Net2Phone File |
| N3 | Notation 3 Document |
| N3D2 | The Nebula Device 2 Mesh Resource File in ASCII Format (RadonLabs GmbH) |
| N3E | OM2 OMALI NENA Encrypted Document Version 3 |
| N4E | OM2 OMALI NENA Encrypted Document Version 4 |
| N64 | MiMiX Emulator |
| N64 | Nintento 64 Emulation ROM Image |
| NA | NoAdware Data File (NoAdware.net) |
| NA2 | Netscape Communicator Address Book |
| NAB | Netscape Communicator Address Book |
| NAB | Novell Groupwise Address Book |
| NAD | Noder File |
| NAF | Compressed Archive |
| NAI | WinINSTALL File |
| NAK | Audio |
| NAL | ArrayScribe (NimbleGen Systems Inc.) |
| NAM | Office Name File |
| NAMEONCLIPBOARD | NAMEONCLIPBOARD Powertoy File |
| NAN | Nanoscope File |
| NAP | Electrical Network Analysis and Planification |
| NAP | EnerGraphics VideoShow File |
| NAP | NAP Metafile Vector Image |
| NAP | Napster Music Security Definition File |
| NAP | VideoShow/EnerGraphics NAPLPS Vector Image Metafile |
| NAP | ePolicy Orchestrator Network Associates Package (Policy File) (Network Associates Technology, Inc.) |
| NAPLPS | North American Presentation Layer Protocol Syntax = Vector image |
| NAR | Nikon Capture Advanced RAW File (Nikon Inc.) |
| NAS | NASTRAN File |
| NASB | TheWord & Bible Companion New American Standard Bible |
| NAV | Application Extension (Microsoft) |
| NAV | Microsoft Network Component (Microsoft) |
| NAV | MSN Application Extension |
| NAV | Counter-Strike: Source CSBot Navigation Mesh (Valve Corporation) |
| NB | Mathematica Notebook (Wolfram Research, Inc.) |
| NB | Nota Bene Document File (Nota Bene Associates, Inc.) |
| NB | WordPerfect Notebook (Corel Corporation) |
| NB7 | NovaBACKUP System Configuration File (NovaStor Corporation) |
| NBA | NBA Game Data |
| NBA | Nota Bene Configuration Information File (Nota Bene Associates, Inc.) |
| NBATTRS | NetBeans Project Attributes File (Collab.Net, Inc.) |
| NBE | Nessus File |
| NBF | Backup NOW! Backup Archive (NewTech Infosystems) |
| NBG | NBG Clean Registry File |
| NBI | BackItUp Document (Ahead Software) |
| NBK | i-Brarian |
| NBK | NovaBACKUP Script (NovaStor Corporation) |
| NBK | Nick-O-Matic Design Factory Project (Riverdeep Interactive Learning Limited) |
| NBM | NetBeans Module (Sun) |
| NC | Graphics File |
| NC | Mastercam NC Programs (CNC Software, Inc.) |
| NC | neatComponents |
| NC | Numerical Control Machine Instructions |
| NC | Preprosessed GOC Source |
| NC | Unidata netCDF Graphics |
| NC | Geopath Machine Part File (SolutionWare Corporation) |
| NC | X-editor Program for CNC Machines (X-net ApS) |
| NCA | NetCam Supervisor Archive |
| NCA | Nikon Capture Color Adjustment File (Nikon Inc.) |
| NCB | Developer Studio File (Microsoft) |
| NCB | Nikon Capture Color Booster File (Nikon Inc.) |
| NCB | Nick-O-Matic Design Factory Project (Riverdeep Interactive Learning Limited) |
| NCC | Computer Numeric Control File |
| NCC | NetCam Supervisor Directory |
| NCC | NetControl V1 1999 |
| NCC | Nokia PC Suite Content Copier File (Nokia) |
| NCC | Nikon Capture Camera File (Nikon Inc.) |
| NCD | CoverDesigner CD Cover Picture (Nero) |
| NCD | Norton Change Directory |
| NCD | NTI CD-Maker File |
| NCD | Xilinx Integrated Software Environment Native Circuit Description (Xilinx, Inc.) |
| NCE | Nick-O-Matic Design Factory Project (Riverdeep Interactive Learning Limited) |
| NCF | Notes Internal Clipboard (IBM) |
| NCF | Netware Command File (Novell, Inc.) |
| NCF | GibbsCAM CNC Program Listing (Gibbs and Associates, Inc.) |
| NCF | Nick-O-Matic Design Factory Project (Riverdeep Interactive Learning Limited) |
| NCH | On Hold Message/Music File |
| NCH | Outlook Express Folder File (Microsoft) |
| NCI | Mastercam Toolpath File (CNC Software, Inc.) |
| NCI | NetCam Supervisor Meta Data |
| NCL | RHS Nibbles Custom Level (Redwood High School) |
| NCM | NetCam Supervisor Video |
| NCM | Communicator Configuration Message (Nokia) |
| NCO | Nero BackItUp Compressed Backup File (Nero AG) |
| NCP | NHL Ice Hockey 2002 User NHLcards File |
| NCR | NCR Image |
| NCS | Netscape Conference Call File |
| NCSA | NCSA Hierarchical Data File Bitmap |
| NCT | Nero Cover Designer Template (Nero AG) |
| NCV | Nikon Capture Curves File (Nikon Inc.) |
| NDA | Nick-O-Matic Design Factory Project (Riverdeep Interactive Learning Limited) |
| NDB | Intellicom Network Database |
| NDB | ProWORX Nxt Short Comment (Schneider Electric) |
| NDB | NetOp Various Information Files |
| NDB | ACT! Notes Data File (Best Software CRM Division) |
| NDB | Nick-O-Matic Design Factory Project (Riverdeep Interactive Learning Limited) |
| NDB | SeeYou Waypoint (Naviter) |
| NDC | Nick-O-Matic Design Factory Project (Riverdeep Interactive Learning Limited) |
| NDCT | DALiM LiTHO Continuous Tone Bitmap (Blanchard Systems Inc.) |
| NDD | Nikon Capture Digital DEE File (Nikon Inc.) |
| NDF | NeoPlanet Browser File |
| NDF | ProWORX Nxt Short Comment (Schneider Electric) |
| NDF | SQL Server Secondary Data File (Microsoft) |
| NDF | NimbleScan NimbleGen Design File (NimbleGen Systems Inc.) |
| NDG | Nick-O-Matic Design Factory Project (Riverdeep Interactive Learning Limited) |
| NDK | Notes Database Design Elements (IBM) |
| NDK | OS/2 Saved Disk Format (IBM) |
| NDL | Inmos Hardware Network Description File |
| NDL | Notes Link (IBM) |
| NDL | Nodelist File |
| NDL | Nick-O-Matic Design Factory Project (Riverdeep Interactive Learning Limited) |
| NDO | 3D Low-polygon Modeler |
| NDP | Nick-O-Matic Design Factory Project (Riverdeep Interactive Learning Limited) |
| NDQ | Totem Cash Data File |
| NDR | RAVE Reports Report File (Nevrona Designs) |
| NDR | Nikon Capture Image Dust Off File (Nikon Inc.) |
| NDS | Indiana Jones and the Infernal Machine Saved Game (Lucasfilm Entertainment Company Ltd.) |
| NDS | Nintendo DS Game ROM Image (Nintendo) |
| NDS | Nick-O-Matic Design Factory Project (Riverdeep Interactive Learning Limited) |
| NDX | ArcView Fonts Index File (ESRI) |
| NDX | Index |
| NDX | Rational XDE (IBM) |
| NDX | WINDEV Index (PC SOFT) |
| NE1 | OM2 OMALI NENA Document Version 1 |
| NE2 | OM2 OMALI NENA Document Version 2 |
| NE3 | OM2 OMALI NENA Document Version 3 |
| NE4 | OM2 OMALI NENA Document Version 4 |
| NEB | Nortec H.E.L.P. |
| NEC | PIMS Notes for Windows CE Audio Record File (Nacetech Co., Ltd.) |
| NED | MSN Application Extension |
| NEF | Nikon Digital SLR Camera Raw Image File (Nikon Inc.) |
| NEN | Nick-O-Matic Design Factory Project (Riverdeep Interactive Learning Limited) |
| NEO | Atari NeoChrome Bitmap Image |
| NEO | NeoPhoto NeoPhoto Album (Archive) (DTLink) |
| NES | Nintendo Entertainment System ROM Image |
| NET | Network Configuration |
| NET | OrCad Netlist Output File |
| NET | netViz Project (netViz Corporation) |
| NET | FileMaker Pro Networking Module |
| NETA | Netica Bayes Net File (Norsys Software Corp.) |
| NETCDF | Scientific data NETwork Common Data Format |
| NEU | MENSI 3D Laser Scanner File |
| NEW | New Information |
| NEWS | News Bitmap Image |
| NEX | Neurological Data for Statistical Analysis |
| NEX | Nexcon System File |
| NEZ | Nintento NES ROM Image |
| NF | CVIP NF_help File |
| NF2 | NeverForget Reminder File (National Creative Registry, Inc.) |
| NFB | Nokia PC Suite Content Copier (Backup) File (Nokia) |
| NFC | Netware Command File (Typo) |
| NFC | Nokia PC Suite Content Copier File (Nokia) |
| NFE | Nikon Capture Fisheye Lens Info File (Nikon Inc.) |
| NFF | Haines Neutral File Format and WorldToolkit minimal 3D scene description language |
| NFF | WorldToolKit Neutral File Format |
| NFG | Gambit Normal Form Representation (The Gambit Project) |
| NFG | RHS Nibbles Finished Game File (Redwood High School) |
| NFL | AutoCAD Multiline Filter List (Autodesk, Inc.) |
| NFL | Sierra Mastercook Layout File |
| NFO | Folio Infobase |
| NFO | JCanyon: Grand Canyon for Java DEM Companion File |
| NFO | System Info File (Microsoft) |
| NFO | Text File |
| NFO | Warez Group Info File |
| NFT | Netobjects Fusion Netobjects System File |
| NFX | Netobjects Fusion Components BBScomp File |
| NG | Norton Guide Online Documentation |
| NGB | Nonogram Puzzle |
| NGD | Xilinx Integrated Software Environment Native Generic Database (Xilinx, Inc.) |
| NGD | NimbleScan NimbleGen Gene Description File (NimbleGen Systems Inc.) |
| NGF | Enterasys Networks NetSight Generated Format File |
| NGG | Nokia Phone Group Graphics/Icons (Nokia) |
| NGL | Sheffield Dictionary File |
| NGO | NG Linker Object (NGML) |
| NGO | Nick-O-Matic Design Factory Project (Riverdeep Interactive Learning Limited) |
| NGP | NeoGeo Pocket ROM Image |
| NGS | NG Compiler Source (NGC) |
| NGS | NGSSniff File |
| NH | NetHack Defaults File |
| NHB | No Hands Backup Backup Description (Anders Petersson's Free Software) |
| NHF | Nero HFS-CD Compilation (Nero AG) |
| NHL | NHL Ice Hockey Game 2002 User Teams File |
| NHV | Nero HD-BURN-Video Compilation (Nero AG) |
| NI | Netobjects Fusion Preview File |
| NIA | Nikon Capture Image Adjustment File (Nikon Inc.) |
| NIB | Corel Graphics10 Photopoint File |
| NIB | Interface Builder User Interface Resources (Apple Computer, Inc.) |
| NIC | Nici Encrypted Image/Graphic File (The DiScosel Group) |
| NICK | Office Data File (Microsoft) |
| NICO | Nolan's Icon Maker Icon File (Nolan's Games) |
| NID | Nikon Capture IPTC Data File (Nikon Inc.) |
| NIF | Navy Image File Format |
| NIF | GameBryo Format File (Numerical Design Limited) |
| NIF | Network Initialization File |
| NIF | Notation Interchange File Format (NIFF) |
| NIF | NetShift Interface File (NetShift Software Ltd.) |
| NIF | NetImmerse Format File (Numerical Design Limited) |
| NIFF | Navy Interchange File Format Bitmap |
| NIL | Norton Icon Library File |
| NIM | Nokia Phone Game File (Nokia) |
| NIP | Network Interface Plug-in |
| NIT | ArcView INFO Table Definitions File (ESRI) |
| NITF | National Imagery Transmission Format |
| NIV | TheWord & Bible Companion New International Version Bible |
| NIX | Rational XDE (IBM) |
| NJP | njPipes Compiler File |
| NJX | NJStar Document |
| NK2 | Outlook AutoComplete File (Microsoft) |
| NKI | KONTAKT Instruments (Native Instruments) |
| NKJV | TheWord & Bible Companion New King James Version Bible |
| NKM | KONTAKT (Native Instruments) |
| NKY | NUMROTOplus Keyfile (NUM Guettinger) |
| NL | Norton Desktop Icon Library |
| NLB | Colin Mc Rae Car Race Network Leader Board |
| NLB | Oracle 7 Data |
| NLC | NeroLINUX Compilation (Nero AG) |
| NLD | ATI Radeon Video Driver |
| NLD | Windows Media Audio/Video File (Microsoft) |
| NLF | MicroSim PCBoard Netlist File for Schematics |
| NLF | ReliaSoft Weibull++ 6 |
| NLM | Nokia Phones LogoManager Bitmap (Nokia) |
| NLM | Netware Loadable Module (Novell) |
| NLO | NetG Skill Builder |
| NLP | Newsletter Profi 2001 |
| NLR | NLREG Nonlinear Regression Control File (Phillip H. Sherrod) |
| NLS | Code Page National Language Support |
| NLTRACK | NoLimits Rollercoaster Simulator Track File |
| NLU | Norton Live Update E-Mail Trigger File |
| NLV | Nikon Capture LCHE Editor File (Nikon Inc.) |
| NLX | FormWorx Form |
| NM | RM Number Magic Data File (RM plc) |
| NMA | Normalised Extinction Corrected Differential Photometry |
| NMAT | NeoEngine (Reality Rift Studios) |
| NMD | SwordSearcher File |
| NMD | Nero miniDVD Compilation (Nero AG) |
| NMDAR | Connectivity Memory Model Input File When Tau1=0.0 |
| NMF | Nuzzler Basic Message File (Securepoint Security Solutions) |
| NMF | Nuzzler Basic Rule Definition File (Securepoint Security Solutions) |
| NMF | Lightwave Narmal Map |
| NMI | SwordSearcher File |
| NMK | Oc2.316s Cakit File |
| NML | NewsMail 2.0 E-mail Newsletter (ESU-Soft) |
| NML | NEURO ONE Static Neuron Model (Netral) |
| NML | NML Language Source File (NevoSoft) |
| NML | .nugthat Compiler Source Code (.nugthat Mark-up Language) (Nuggets Unlimited, Inc.) |
| NMO | Virtools Behavioral Objects |
| NMS | Numega Softice's Loader File |
| NMS | Virtools Graphical Scripts |
| NMW | Netmeeting T126 Compatable Whiteboard Document (Microsoft) |
| NNB | newnovelist Story Outline |
| NNI | ANNI Artificial Neural Network Investing |
| NNR | Nikon Capture Noise Reduction File (Nikon Inc.) |
| NOA | Cell Phone Video Clip |
| NOA | Nancy Video CODEC |
| NOB | Silver Sprites and Data |
| NOB | Vampire: La Mascarade Archive |
| NOB | VersaPro Word Exchange File |
| NOD | NetObjects Fusion |
| NOD | Noder File |
| NOI | TGIF-3.0 File |
| NOL | Nokia Phone Operator (Manager) Logo (Nokia) |
| NOM | Aonix Nomad |
| NON | Nonogram Puzzle |
| NON | Star Wars - Tie Fighter Mouse Options |
| NOR | ATI Radeon Video Driver |
| NOR | Personal Paint Norwegian Language User Interface File (Amiga) |
| NOT | Acrobat Spelling File (Adobe) |
| NOT | ActiveNote Post-It-Notes |
| NOT | Notation or Note |
| NOT | e-Sword Study Note File (Rick Meyers) |
| NOT | Broderbund Note Card Type (Riverdeep Interactive Learning Limited) |
| NOT | Note-It Note File (Veign) |
| NOTE | WordPerfect for Macintosh Help Document (Corel Corporation) |
| NOTES | Réviseur de notes Notes File (Fichier de notes) (Francis Gagné) |
| NOW | Text File |
| NP | Cliq Accessories Notepad Text |
| NP | Planner Project Schedule (Nokia) |
| NPA | ReliaSoft Weibull++ 6 |
| NPAC | NeoEngine Resource Package (Reality Rift Studios) |
| NPC | Jagged Alliance 2 Non-Player Character File (Sir-tech Canada Ltd.) |
| NPC | Nick-O-Matic Design Factory Project (Riverdeep Interactive Learning Limited) |
| NPD | Noder File |
| NPD | Ultra Network Sniffer Captured Packet (GJPSoft, Inc.) |
| NPF | Nick-O-Matic Design Factory Project (Riverdeep Interactive Learning Limited) |
| NPI | dBASE Application Generator Source |
| NPI | Nikon Capture Filters File (Nikon Inc.) |
| NPI | Nick-O-Matic Design Factory Project (Riverdeep Interactive Learning Limited) |
| NPK | MikroTik RouterOS Upgrade Package |
| NPL | DART Pro 98 Noiseprint Info |
| NPL | Xilinx Integrated Software Environment Project File (Xilinx, Inc.) |
| NPM | Corel Graphics Ver 10 Draw Media Lines File (Corel) |
| NPM | Neopaint Mask |
| NPM | Nokia Phone Picture Message (Nokia) |
| NPP | Art Explosion Publisher Pro Document (Nova Development Corporation) |
| NPS | Lotus Agenda File |
| NPS | NeroMix (Nero AG) |
| NPT | DART Pro 98 Noiseprint Archive Import |
| NQC | Not Quite C Source Code (Dave Baum) |
| NR3 | Nero MP3 CD-ROM Compilation (Nero AG) |
| NR4 | Nero AAC CD Compilation (Nero AG) |
| NRA | Nero Audio-CD Compilation (Nero AG) |
| NRB | Nero CD-ROM Boot Compilation (Nero AG) |
| NRC | Nero UDF/ISO CD-ROM Compilation (Nero AG) |
| NRD | Nero DVD-Video Compilation (Nero AG) |
| NRE | Nero CD Extra Compilation (Nero AG) |
| NRF | Neutral Raster File Bitmap |
| NRF | Nicolet DataViewer Multi-segment Waveform Data (Nicolet Instrument Technologies, Inc.) |
| NRG | Nero CD-Image File (Nero AG) |
| NRG | Norton Registration Entries (Symantec) |
| NRH | Nero Hybrid CD-ROM Compilation (Nero AG) |
| NRI | Nero ISO CD-ROM Compilation (Nero AG) |
| NRL | iManage File |
| NRM | Nero Mixed-Mode-CD Compilation (Nero AG) |
| NRS | Nero CD-ROM (EFI Boot) Compilation (Nero AG) |
| NRSV | TheWord & Bible Companion New Revised Standard Version Bible |
| NRT | Nokia Phone Ring Tone (Nokia) |
| NRU | Nero UDF CD-ROM Compilation (Nero AG) |
| NRV | Nero Video-CD Compilation (Nero AG) |
| NRW | Nero WMA CD-ROM Compilation (Nero AG) |
| NRX | NeatReceipts SCANALIZER Expense Report File (NeatReceipts) |
| NS1 | NetStumbler NS1 Log |
| NS2 | Notes Ver 2 Database (Older Form) (IBM) |
| NS3 | Notes Database (Older Form) (IBM) |
| NS4 | Notes Database (Older Form) (IBM) |
| NS5 | Notes/Domino (IBM) |
| NSB | Novaschem School Schedule |
| NSC | Noder File |
| NSC | Windows Media Station File |
| NSCE | NeoEngine Scene File (Reality Rift Studios) |
| NSD | NRG Site Database |
| NSD | Norton System Doctor Sensors Configuration (Symantec) |
| NSD | Nero Super Video CD Compilation (Nero AG) |
| NSDF | NevoSoftDB Standard Format Database File (NevoSoft) |
| NSF | Notes Database (IBM) |
| NSF | NES Sound File |
| NSG | Notes Database (Older Form) (IBM) |
| NSH | Notes Database (Older Form) (IBM) |
| NSH | Nullsoft Scriptable Install System (NSIS) Header/Include File |
| NSI | Install System Script (Nullsoft) |
| NSI | Symantec Shared File |
| NSI | NewsStand Reader (NewsStand, Inc.) |
| NSK | NaShrinK Archive (NashSoft Systems) |
| NSL | Nokia Phone Startup Logo (Nokia) |
| NSM | NESticle Movie |
| NSO | NetStudio Easy Web Graphics File |
| NSO | Nick-O-Matic Design Factory Project (Riverdeep Interactive Learning Limited) |
| NSP | Multi-Speech Sound File (Kay Elemetrics Corp.) |
| NSP | Computerized Speech Lab Audio Speech Format (Kay Elemetrics Corp.) |
| NSR | Nessus Project |
| NSR | Nikon Capture Size and Resolution File (Nikon Inc.) |
| NSS | Norton ScreenSaver Module |
| NST | Audio |
| NST | Noise Tracker Music Module |
| NSV | Winamp3 Video Format File |
| NSV | Nullsoft (Streaming|S as in Soft) Video (Nullsoft, Inc.) |
| NSX | SuccessWare SIX 3.00 Compound Index File |
| NSX | HiPer-Six Index File |
| NSX | Apollo Database Engine Index |
| NT | Windows NT Command Script (Microsoft) |
| NT0 | Adressmn |
| NT1 | Adressmn |
| NT2 | Adressmn |
| NT3 | Adressmn |
| NT6 | Orchida Knitting System Universal Flat Knitting Machine Pattern (Orchida Soft) |
| NT7 | Orchida Knitting System Universal Flat Knitting Machine Pattern (Orchida Soft) |
| NTC | Nikon Capture Camera Curves Information File (Nikon Inc.) |
| NTE | Holonote Note |
| NTF | Notes Database Template (IBM) |
| NTF | National Transfer Format Map File |
| NTH | Imagemagick-5.3.2 Visualmagick JBIG File |
| NTH | Series 60 Theme Studio for Symbian OS Theme File (Nokia) |
| NTO | NTOScanner |
| NTP | Neato CD Labels |
| NTR | Netrun Executable Text File |
| NTS | Netsend Executable Text File |
| NTS | Norton Tutorial |
| NTS | Psion Organiser Notepad File (Psion PLC) |
| NTS | Norman TurboStore Database Data Storage (Norman ASA) |
| NTT | CD Label Template |
| NTV | PatternSmith Import File (Autometrix) |
| NTW | LVNet - Low Voltage Networks Analysis |
| NTW | Noteworthy Composer Song File (NoteWorthy Software, Inc.) |
| NTX | NTX Web Audio File |
| NTX | CARIS Marine Navigation Info |
| NTX | Clipper Index |
| NTX | Network Terminal Accelerator Adapter Card Configuration Information |
| NTX | yEnc32 yEncoded File |
| NTX | PIMS Notes for Windows CE Text Note File (Nacetech Co., Ltd.) |
| NTZ | InVircible Directory Integrity Information |
| NU4 | Norton Utilities DLL Root File (Symantec) |
| NU6 | Norton Utilities System DLL File |
| NUF | Procomm Plus New User Message |
| NUG | .nugthat Player Nugget File (Nuggets Unlimited, Inc.) |
| NUL | CCS-lib.2 ACS File |
| NUL | Grand Theft Auto (Playstation 2) Game File (Take-Two Interactive Software, Inc.) |
| NULL | NULL Image |
| NUM | DOS 7 File |
| NUM | Guitar Chords in Nashville Numbering System Format |
| NUM | Nikon Capture Unsharp Mask File (Nikon Inc.) |
| NUP | NOD32 Digitally Signed Update File (Eset) |
| NUT | .nugthat Player (Nuggets Unlimited, Inc.) |
| NUV | MythTV NuppelVideo Video File |
| NV | Juno Access Number Info File (Juno Online Services, Inc.) |
| NV | Visicontrol MVS-20 Non-Volatile Memory Backup File |
| NV! | Net Transport Partial Download (Exciting Software) |
| NV3 | Visicontrol MVS-30/35/40 Flash-Memory Backup File |
| NVC | NeroVision Express Project File (Nero AG) |
| NVC | Nikon Capture Vignette Correction Information File (Nikon Inc.) |
| NVD | AOLpress Help |
| NVD | NetworkView Network Discovery |
| NVF | Nomad II Voice File (Creative Technology, Ltd.) |
| NVF | Visicontrol MVS-20 Non-Volatile Memory Backup File |
| NVM | AOLpress Help |
| NVR | NeverForget Reminder File (National Creative Registry, Inc.) |
| NVV | Nvidia Vertex Shader (Nvidia) |
| NVX2 | The Nebula Device 2 Mesh Resource File in Binary Format (RadonLabs GmbH) |
| NW | NoteWorthy 2 File |
| NW | Graal Level (Cyberjoueurs) |
| NW | Dispatch Northwest Timetable File (Scott Andrew Borton) |
| NW3 | Netware.3x File |
| NW4 | Netware.4x File |
| NWB | Nikon Capture White Balance File (Nikon Inc.) |
| NWC | NavisWorks File |
| NWC | Noteworthy Composer Song File (NoteWorthy Software, Inc.) |
| NWD | NavisWorks File |
| NWF | NavisWorks File |
| NWID | NeoEngine (Reality Rift Studios) |
| NWS | Newsmaster or Newsmaster II Data File |
| NWS | Outlook Express News File (Microsoft) |
| NWS | Creatacard Newsletter or Photo Album or Presentation or Report Cover or Resume Project (Broderbund) |
| NWV | Dragon NaturallySpeaking User Profile File (Scansoft, Inc.) |
| NWX | NWX Editor (TheOutlawDad) |
| NWX | Outlaws Choreography (LucasArts Entertainment Company LLC) |
| NW_ | Noteworthy Compressed Audio File |
| NXD | ndxCards Index Card Project (TruTamil LLC) |
| NXT | NeXT Sound File |
| NY | Nyquist Plug-in |
| NYF | Mybase Database (WJJ Software) |
| NYM | Sheffield Dictionary File |
| NZ | Audio Utility Tuningwrench Compressed File |
| NZB | newzBin USENET Index |
| NZL | Corel Painter Nozzle File |