| nha | Native Noah Format Data |
| nhb | No Hands Backup Backup Description |
| nhcode | Mastercam NetHASP Code |
| nhd | Nero Burning ROM AVHCD Compilation |
| nhd | NetHelpDesk Page Data |
| nhdr | Nearly Raw Raster Header Data |
| nhm | Microsoft SMS NHM Data |
| nhp | NOAA Hydrophone Data |
| nhr | BLAST Header Data |
| nhx | New Hampshire eXtended Format Data |
| nia | Nikon Capture Image Adjustment Data |
| nib | Adobe AIR NIB Data |
| nick | Microsoft Outlook 2000 Auto Complete Nick List |
| nicrash | NI Traktor Crash Data |
| nid | Nikon Capture IPTC Data |
| nif | Gamebryo Model Data |
| nif | NetShift Interface Format Data |
| nifcache | Gamebryo NIF Cache |
| nii | NIfTI-1 Data Format File |
| nil | Norton Icon Library File |
| nil | QIP NIL Data |
| nimblegen | NimbleGen Array Layout Editor Data |
| nin | BLAST Nucleotide Database |
| nir | FOSS NIR Spectrophotometers Data |
| niv | theWord New International Version Module |
| nix | IBM Rational XDE Node Instance File |
| nj | MOLPHY Neighbor Joining Phylogeny Data |
| nja | Seifert XRD ASCII Pole Figures Data |
| njb | Nikon Photo Index |
| njc | Seifert XRD Pole Figures Data |
