| ncb | Visual Studio No Compile Browse File |
| ncl | NCAR Command Language File |
| ndb | ProWorx NXT Short Comment with Blocking |
| ndf | ProWorx NXT Short Comment File |
| ndx | WinDev HyperFileSQL Index |
| ned | OMNeT++ Network Description |
| neko | Neko Source Code |
| nfm | Delphi .NET Form |
| nfx | NetObjects Fusion Components |
| ngi | NGI Package |
| ngo | Norton Guide Linker Object |
| nhs | NHibernate Settings File |
| ni | NetObjects Fusion Preview |
| nib | Apple Interface Builder Resources |
| nim | Nimrod Source Code |
| nir | AdminStudio Repackaging Wizard Output |
| nj | Nunjucks Template |
| njk | Nunjucks Template |
| njs | Nunjucks Template |
| nk | NUKE Script |
| nmf | Native Client Manifest File |
| nmk | NMake Makefile |
| nod | NetObjects Fusion Site File |
| npmignore | NPM Ignore |
| nqc | Not Quite C Source Code |
| nse | Nmap Scripting Engine Script |
| nsh | NSIS Header |
| nsi | NSIS Script File |
| nsis | NSIS Script File |
| nunj | Nunjucks Template |
| nunjs | Nunjucks Template |
| nunjucks | Nunjucks Template |
| nupkg | NuGet Package |
| nuspec | NuGet Package Metadata |
| nuspec | NuGet Specification Data |
