What is OBJ?

OBJ was created by Wavefront Technologies in the 1980s, and almost every 3D application can still read it. It's a text file: open one in a text editor and you'll see lines starting with v (vertex), vt (texture coordinate), vn (normal) and f (face).

OBJ + MTL + textures

Materials live in a separate .mtl file, which points to texture images by filename. When you move an OBJ, you must move all three parts together, or it opens grey and untextured. This is the most common OBJ problem.

What OBJ can't do

• No animation, rigging or scene hierarchy
• No modern PBR materials (the MTL format predates them)
• Large file sizes, because it's text

When it's the right choice

For static meshes going into older tools, CAD-adjacent software, or anything that doesn't support glTF or FBX. OBJ also supports quads and n-gons, which some modellers prefer to keep.