| tra | MRMC Matrix Data |
| tra | RFM Transmission Spectrum File |
| tra | WinTrack Railroad Track |
| trace | VMware ThinApp Binary Trace Log |
| trace | Wireshark Trace Data |
| trak | NI Traktor Pak File |
| trans | Amaya Transformations Data |
| trashinfo | Linux Trash Storage Metadata |
| traw | PLINK Variant-major Additive Component File |
| tray | CorelDRAW Corel CONNECT Tray Data |
| trb | Animation Master Turbulence Plug-in Data |
| trb | HP Printer Diagnostic Package |
| trb | WAsP Wind Turbine Data |
| trbw | STAR-CCM+ TurboWizard File |
| trc | Lattice Reveal Analyzer Waveform Data |
| trc | SVAL Truncated Data |
| trce | Corel Trace Data |
| trd | Lingea Lexicon Dictionary Data |
| trd | TrID Definitions Package |
| tre | TreeAge Decision Tree |
| tree | Es-Builder v3 Tree File |
| treedb | TreeDBNotes Options Data |
| treefile | GDE Phylogenetic Tree Data |
| trf | BrainVoyager QX Transformations Data |
| trf | LFToolkit Transformation Rules File |
| trg | SQL Script Triggers |
| trg | Symantec LiveUpdate TRG Data |
| tri | Alias PowerAnimator 3D Data |
| tri | Cart3D Triangulation Data |
| tri | FreeSurfer Triangular Surface Data |
