.o Object code
Documents & office
| MIME type | application/x-object |
|---|---|
| Description | Object code |
| Category | Documents & office |
| Signature (magic bytes) | 7F 45 4C 46 (.ELF) |
| Other extensions | .mod |
Frequently asked questions
What is a .o file?
A .o file is a “Object code” (MIME type application/x-object).
How do I open a .o file?
With an office suite: LibreOffice (free, Windows/macOS/Linux) opens most document formats, as do Microsoft Office or the vendor’s own app.
How can you tell a genuine .o file?
By the bytes at the start of the file, the signature (magic bytes): 7F 45 4C 46 (.ELF). On Linux and macOS, file --mime-type example.o checks the real type regardless of the extension.
Which MIME type belongs to .o?
The MIME type is application/x-object. In the Apache web server: AddType application/x-object .o; in nginx: types { application/x-object o; }.