| mod | ProModel Optimization Software Model |
| mod | SVAL Modal Data |
| mode | Coda Syntax Mode |
| model | CATIA Model Data |
| model | Ribbons Model Definition |
| modfem | Femap Model File |
| modus | Adobe Mocha for After Effects Modus Data |
| moe | Modelica Encrypted Model |
| moe | Molecular Operating Environment File |
| moef | Motion Effect Template |
| mogg | MedCalc MOGG Data |
| mogrt | Adobe Premiere Motion Graphics Template |
| mohoaction | Moho Action Data |
| mohobrush | Moho Brush Data |
| mohoexport | Moho Export Profile Data |
| mohostyle | Moho Style Data |
| moi | JVC Everio Video Information Data |
| mojito | LimeWire Kademlia Data |
| mol | Easy Palette Object Library |
| mol | MDL Molfile Data |
| mol | Music Module List |
| mol2 | Tripos Mol2 Format File |
| molo | Motion Object |
| mologiq | HTC EVO 3D Data |
| mon | Mozilla Firefox Bookmark Backup Data |
| mon | Steinberg WaveLab Audio Montage |
| mon2 | UltraSite Graphical Status Data |
| monet | Adobe Mocha for After Effects Monet Data |
| moneywell | MoneyWell Account Data |
| mongodb | MongoDB Database |
