OBJ vs FBX vs STL vs glTF: Which 3D Format to Choose

The one-minute answer

All four formats store a three-dimensional model, but each is tuned for a different stage in that model's life. In a nutshell:

• OBJ — simple geometry exchange. Opens almost everywhere, but knows nothing about animation.
• FBX — professional exchange between Maya, 3ds Max, Blender, Unity and Unreal. Stores animation, bones, cameras and lights.
• STL — strictly for 3D printing. Shape only, no color and no textures.
• glTF/GLB — delivery of 3D to the browser, AR and the metaverse. Lightweight, modern, with realistic materials.

OBJ — the universal grandfather

OBJ (Wavefront Object) appeared back in the late 1980s and has since become the unofficial "Esperanto" of 3D graphics. It is a simple text format: inside you'll find vertices, normals, texture coordinates and faces, all written as lines you could read in Notepad if you wanted to.

One key detail: OBJ does not store materials inside itself but in a companion file called .mtl (Material Template Library). So an OBJ model almost always travels as a pair of files — don't lose the .mtl, or you'll be left with no colors and no textures.

OBJ's strength is total compatibility: literally any 3D editor imports it, which makes it ideal for moving static geometry between programs and for long-term archiving. Its weakness is that it knows nothing about animation, bones or modern PBR materials — under the hood it still relies on old Phong shading.

FBX — the animation workhorse

FBX (Filmbox) is a product of Autodesk, the owner of Maya and 3ds Max. It is a proprietary yet de facto standard format for "heavy" exchange in game development and film. Unlike OBJ, FBX can pack an entire scene: meshes, materials and textures, keyframed skeletal animation, rigging (bones and skinning), morph targets, cameras, light sources and the object hierarchy.

That's exactly why FBX is the only real choice when a model has to move. A rigged character, an animated creature, a car with opening doors — OBJ simply cannot hold any of that, whereas FBX carries it from the 3D editor into the engine losslessly.

STL — the language of 3D printers

STL (expanded as STereoLithography, or "Standard Tessellation Language") is the most single-purpose format of the four. It describes only the model surface as a mesh of triangles and stores neither color, nor textures, nor units of measurement by default. And that is not a flaw: a 3D printer only needs the shape — it extrudes plastic layer by layer, and color comes from the filament spool.

STL's key requirement is a watertight (manifold) mesh: every edge belongs to exactly two triangles, with no holes and no flipped normals. If the model is "leaky," the slicer won't understand where its inside is, and the print will fail. We have a separate detailed guide on preparing STL for printing.

glTF/GLB — the "JPEG of 3D"

glTF (GL Transmission Format) is an open format from the Khronos Group, created specifically for fast real-time delivery of 3D. Its own authors nicknamed it "the JPEG of 3D": it is just as lightweight and render-ready for three-dimensional scenes as JPEG became for images. In 2022, glTF 2.0 was adopted as the ISO/IEC 12113 international standard.

Unlike OBJ, glTF supports physically based PBR materials and animation out of the box, and it renders with almost no overhead — the data is stored close to the form the graphics card expects. The format has two faces: .gltf is a JSON description of the scene (sometimes with external buffer and texture files), while .glb is the same format packed into a single binary file that bundles geometry and textures together. For the web and AR, we have a deep dive into glTF and GLB.

All differences in one table

Let's put the key differences side by side so the choice takes seconds:

How to choose for your task

The practical rule: pick a format not by "which is best overall" but by "where the model goes next." Here's a short step-by-step.

And if you're not sure what format you're holding or how to open it, start with our overview on how to open 3D models — it covers free viewers for OBJ, FBX and STL. Game makers will find our guide to 3D formats for games handy too.