| nlo | Lotus Notes Linked Object |
| nlogo | NetLogo Model |
| nlogo3d | NetLogo 3D Model |
| nlp | NirLauncher Package |
| nlr | NLREG Nonlinear Regression Control Data |
| nls | National Language Support |
| nlt | Oracle Locale Builder Text File |
| nlv | Nikon Capture LHC Editor File |
| nly | CBS CheckWriter NonCalc Layout |
| nm | RM Number Magic Document |
| nm2 | Navitel v3 Map |
| nm3 | Navitel v5 Map |
| nm7 | Navitel Navigator v7 Map |
| nmb | Samba NetBIOS Name Server Log |
| nmbd | Samba NetBIOS Name Server Log |
| nmdb | NoiseMap Database |
| nmig | Noah System 3 Database |
| nmig2 | Noah System 3 Database |
| nmm | Nightmare Module |
| nmo | 3DVIA Virtools Behavioral Object |
| nmp | Nikon E-Max Data |
| nmpt | Navicat for MariaDB Transfer Data |
| nmr | NUTS NMR Data |
| nmx | NI Traktor Mix Data |
| nnd | CYMFLOW Network Data |
| nnf | Cytoscape Nested Network Format File |
| nni | ANNI Neural Network Investing |
| nnl | Network Notepad Professional License |
| nnn | Filmetrics F20 Material Data |
| nnp | ANNI Neural Network Portfolio |
