| 2dm | SMS 2D Mesh Data |
| 2dp | GP Workbench 2DRadar Input Parameter File |
| 2dv | Cadwork Parametric Elements Data |
| 300 | NCBridge XP300 Boot Image |
| 323 | H.323 IP Telephony Data |
| 32x | Sega 32X ROM Image |
| 330 | NCBridge XP330 Boot Image |
| 356 | IPC-D-356 Data |
| 3cn | 3D Movie Maker Scene Data |
| 3d | Advent 3B2 Document |
| 3d | Geocadabra 3D Data |
| 3d | Survex 3D Cavern Data |
| 3dc | 3DCrafter Scene Data |
| 3dc | CompuTrainer 3D Chart Screen |
| 3dc | iGO 3D Building Data |
| 3dc | RoboCell Cell Setup Data |
| 3dcpack | 3D-Coat Extension Package |
| 3dd | Neuroscan 3D Coordinates Data |
| 3de | 3Data Expert Data |
| 3df | BI/Query Chart Template |
| 3df | MapInfo 3D Graph Data |
| 3df | QuickDraw 3D Data |
| 3dh | SeisWorks Horizontal Time-slice Format File |
| 3di | Altair FEKO 3D Artwork Data |
| 3dl | iGO 3D Landmark Data |
| 3dl | Sierra LandDesigner 3D Model Data |
| 3dm | Rhino 3D Model Data |
| 3dmap | Catia 3DMAP File |
| 3dmap | Metaio SDK 3D Map |
| 3dmbak | Rhino 3D Model Backup |
| 3dmdef | 3DMark Definitions Data |
| 3dn | DreamPlan Home Design Software Model |
| 3don | Scrutinize 3D Mesh Data |
| 3dp | Autodesk 123D Photo Scene |
| 3dps | 3D eBook Shot Animation |
