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.OBJ file extension

To open .OBJ files on Windows, open Blender, then go to File → Import → Wavefront (.obj).

To open an .obj file, use a 3D modeling or viewing program that supports Wavefront OBJ—Blender can import and export it. If the model looks untextured, make sure the companion .mtl file (and referenced texture images) are present next to the .obj.

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Last updated: June 12, 2026

Open on your device

Choose your operating system for a dedicated step-by-step opening guide.

How to open .OBJ files

Use these platform-specific instructions to open .OBJ files safely.

Windows

  1. Open Blender, then go to File → Import → Wavefront (.obj).
  2. Select the .obj file; if there is an .mtl and textures, keep them in the same folder so materials can resolve.
Full Windows guide

Mac

  1. Open Blender, then go to File → Import → Wavefront (.obj).
  2. Import the .obj; if materials are missing, place the .mtl and textures next to the .obj and re-import.
Full Mac guide

Linux

  1. Open Blender, then go to File → Import → Wavefront (.obj).
  2. Choose the .obj file; confirm that any .mtl and texture images referenced by the model are accessible.
Full Linux guide

iOS

  1. If you need reliable viewing or editing, transfer the .obj (and any .mtl/textures) to a desktop system and open it in Blender.
Full iOS guide

Android

  1. If you need reliable viewing or editing, transfer the .obj (and any .mtl/textures) to a desktop system and open it in Blender.
Full Android guide

Security notes

  • OBJ is a text-based geometry format, but opening untrusted OBJ/MTL content can still be risky if a viewer/importer has parsing vulnerabilities; prefer up-to-date, well-maintained tools.
  • MTL files can reference external texture images; if those textures are missing, the model may load incorrectly, and if they are unexpectedly large they can cause performance or memory issues during import.
  • Very large OBJ files (dense meshes) can consume significant RAM/CPU on import and may cause application slowdowns or crashes; consider inspecting file size before opening.

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Can't open this file?

These are the most common causes and fixes when .OBJ files fail to open.

Common reasons

  • Model imports with no textures or wrong materials
  • Model imports at the wrong size or orientation
  • Missing parts, holes, or shading looks faceted

Fix steps

  1. Check whether there is a companion .mtl file with a matching name and ensure it is in the same folder as the .obj.
  2. Verify that any texture images referenced by the .mtl are present and paths still match; re-import after fixing file locations.

OS-specific troubleshooting

What is a .OBJ file?

Wavefront OBJ is a plain-text format for describing 3D geometry, including vertex positions, texture coordinates, vertex normals, and faces. Materials are typically stored in a companion .mtl (material template library) file referenced from the OBJ. The syntax is line-based, using record types such as v, vt, vn, f, and mtllib/usemtl.

Background

Wavefront OBJ is a common interchange format for 3D meshes because it is human-readable and supported by many 3D tools. It primarily represents polygonal geometry (often triangles or quads) and can include grouping and smoothing information.

A typical OBJ workflow also involves a material library: the OBJ references an MTL file (via an mtllib statement), and the MTL may reference texture images. If you receive only the .obj without its .mtl and textures, the model can still load, but it may appear with default materials.

Because it is text-based, OBJ files are easy to inspect and can be generated or edited by scripts, but they can also become very large for detailed meshes. For reliable results when sharing, keep the .obj, .mtl, and any texture files together and avoid renaming one without updating the references inside the files.

Common MIME types: model/obj

Further reading

Authoritative resources for more details on the .OBJ format.

Common .OBJ issues

Model imports with no textures or wrong materials

OBJ geometry and material definitions are commonly split: the .obj references a separate .mtl file, and the .mtl may reference texture images. If the .mtl or textures are missing or moved/renamed, the model will appear untextured or with default materials.

  1. Check whether there is a companion .mtl file with a matching name and ensure it is in the same folder as the .obj.
  2. Verify that any texture images referenced by the .mtl are present and paths still match; re-import after fixing file locations.

Model imports at the wrong size or orientation

OBJ stores geometry but does not standardize scene units or coordinate conventions across all tools, so an importer may interpret scale and axes differently.

  1. In your importer (for example, Blender’s OBJ import), adjust scale and axis conversion options if available.
  2. If you export the OBJ again, document the intended units/axes for the receiving tool.

Missing parts, holes, or shading looks faceted

OBJ can include normals and smoothing/grouping information, but exporters/importers may omit or reinterpret them. Face winding/backface culling can also make parts look invisible from one side.

  1. Try importing with options that preserve normals/smoothing when available; if shading is wrong, recalculate normals in the 3D tool.
  2. If surfaces disappear from certain angles, check face orientation and flip/recalculate normals as needed.

FAQ

What’s the difference between .obj and .mtl?

.obj primarily stores the mesh geometry, while the companion .mtl material library stores material properties (and often references texture images). The .obj links to the .mtl using an mtllib statement and applies materials with usemtl.

Is OBJ a binary format?

Wavefront OBJ is typically plain text with line-based records (for example v, vt, vn, f), which makes it readable in a text editor.

What MIME type should be used for .obj on the web?

The IANA-registered media type for Wavefront OBJ is model/obj.

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