What is the YOBJ file format?
A .yobj file is a Yuke's 3D Object, the model format used by the Japanese studio Yuke's in its console games. It is best known from the WWE wrestling series, where it holds the geometry for wrestlers, arenas and props in WWE 2K19 and every earlier entry, along with Yuke's UFC Undisputed titles.
Each file stores the mesh (vertices, faces and UV coordinates), skeletal bones, shader assignments and references to the textures used on the model. The texture images themselves are not inside the .yobj; they sit in separate container files. The mesh payload is compressed and encrypted, which is why a .yobj cannot be read like an ordinary model. TrID records the four ASCII characters YOBJ at the very start of the file. Some models carry the .jboy extension, a variant of the same format.
After Yuke's left the WWE franchise with WWE 2K20, later games moved to other model formats, so the .yobj you meet almost always comes from an older Yuke's release.
Security & safety
RISK: LOWA .yobj is passive model data, not an executable, so the file itself does not run code. The practical caution is legal rather than technical: these files are extracted from copyrighted commercial games, and the third-party modding tools that open them come from community forums, so download importers and editors only from trusted sources.
Format details
in a nutshellPrograms that open YOBJ files
Windows3 apps
Autodesk 3ds Max (with YOBJ Importer plug-in)
Paid Install the community YOBJ 3ds Max Importer plug-in, then use it to import a .yobj model into 3ds Max to view, edit and re-export it.
X-Rey (by tekken57)
Free Open a .yobj extracted from a WWE 2K PAC archive to preview and edit the model mesh with this community WWE modding tool. Technical details
deep spec| Encoding | Binary |
| Byte order | Little-endian on PC/PS3 builds; platform-dependent |
| Container | Yuke's proprietary 3D object container, holding a compressed and encrypted mesh payload |
| Compression | Internal payload is compressed |
| Encryption | Internal mesh data is encrypted, which is why players cannot open the file directly without modding tools |
| Structure | A YOBJ stores the mesh (vertices, faces, UV coordinates), skeletal bone data, shader assignments and texture reference/material data for a single 3D model. It does not embed the texture bitmaps themselves, which live in separate files such as PAC containers. |
| Integrity | None documented |
| Platforms | Windows, PlayStation 2, PlayStation 3, PlayStation 4, Xbox 360, Xbox One |
| Notes | Used across Yuke's-developed titles, most visibly the WWE SmackDown vs. Raw and WWE 2K wrestling series through WWE 2K19, and Yuke's UFC Undisputed games. From WWE 2K20 onward, after Yuke's left the franchise, models moved away from this format. Files with the .jboy extension are a variant of the same format. |
| Typical size | Tens of kilobytes to several megabytes depending on model complexity |
| Specification | wiki.prowrestlingmods.io |
YOBJ conversions
Community Q&A
asked by usersNo questions yet - be the first to ask about YOBJ files.
Frequently asked questions
What program opens a YOBJ file?
Can I convert a YOBJ file to OBJ?
.yobj into 3ds Max with the YOBJ plug-in, then export as .obj. You cannot simply rename the file, because the internal data is compressed and encrypted.
