.DT_ File Extension
Macintosh Data Fork
| Developer | Apple |
| Popularity |
3.8 | 4 Votes |
What is a DT_ file?
A DT_ file is a legacy Macintosh file component that contains the data portion of a file's "data fork." In classic Mac systems, files were often split into two parts: a data fork (the main file content) and a resource fork (extra system or application data such as icons, menus, or metadata). DT_ files represent the extracted data fork when Mac files were moved or shared outside of their original file system.
More Information
DT_ files were most commonly created during file transfers between Mac systems and non-Mac systems, especially when using older compression or archiving tools. Since many non-Mac file systems could not store dual-fork files properly, utilities would split them into separate components, often producing a DT_ file for the data fork and a corresponding resource fork file (sometimes seen as .RSRC or similar naming conventions).
NOTE: Today, DT_ files are largely obsolete. Modern versions of macOS moved away from the classic dual-fork file structure in favor of more standardized file systems that handle metadata differently.
How to open a DT_ file
DT_ files are not standalone file formats and are not typically opened directly. They represent the data fork of a classic Macintosh file, which contains only part of the original file’s structure. Because classic Mac files also relied on a separate resource fork, DT_ files are usually incomplete on their own and must be reconstructed using specialized tools or original Mac file containers that preserve both forks.