OneTaskBy Tim King · Updated
GLB to OBJ Converter
Convert glTF Models to OBJ, Free
OneTask is free, with no sign-up, and built by one person.
If this tool saved you time, a coffee helps keep new ones coming.
How the GLB To OBJ works
This GLB to OBJ converter turns a glTF model into a Wavefront OBJ file that almost any 3D program can open. Drop a .glb, or a .gltf with its .bin and texture files, check the model in the orbit viewport, pick the up axis and units, and download the .obj. The conversion runs in your browser, so the model is never uploaded.
GLB to OBJ: what is kept and what is dropped
A GLB is a whole scene: a tree of nodes with transforms, meshes, physically based materials, textures and sometimes animation or skeletons. OBJ is a much older text format that stores vertices, normals, texture coordinates and faces, grouped into named objects. The converter walks the scene, bakes each node's position, rotation and scale into its vertices and writes one named object per mesh, with normals and UVs kept. Materials, textures, animation and skinning are not written, because OBJ cannot hold them without a separate .mtl file and image copies; skinned characters come out in their rest pose.
Up axis and units
glTF is defined as Y up and in metres, and so is the OBJ by default, which suits Blender, Maya, game engines and most viewers. Choose Z up for CAD and 3D printing tools that expect Z to point up, and m to mm when the target program reads the numbers as millimetres, so that a 0.2 metre model arrives 200 units tall rather than 0.2.
When OBJ is the right choice
OBJ is the lowest common denominator of 3D files. Older modelling software, some CAD and CNC tools, sculpting apps, academic code and many online services read OBJ but not glTF. It is also plain text, so it can be inspected, diffed or edited by script. The downside is size: an OBJ is typically several times larger than the same GLB, because every number is written out as text.
FAQ
Are textures and colours kept?
No. The OBJ holds geometry, normals and texture coordinates only, so the UV layout survives but the images and material colours do not. Export the textures from the original glTF separately and reassign them in your 3D program if you need them.
Can I convert a .gltf with separate files?
Yes. Drop the .gltf together with its .bin buffer and any texture images in one go, so every file the model references can be found. A single .glb already contains everything.
Why is the OBJ so much bigger than the GLB?
GLB stores numbers as packed binary, four bytes each. OBJ writes every coordinate as text with many digits, plus a line prefix, so the same mesh often grows three to five times. Zip the OBJ before emailing it; text compresses very well.
See also: all Images tools, Units, Audio & Video, Documents, Data & Code.
Related tools
OBJ To GLB
Convert OBJ, MTL and textures into one GLB file in the browser.
GlTF / GLB Viewer
Drop a GLB or glTF, orbit it, play animations, download a PNG.
OBJ Viewer
Drop an OBJ with its MTL and textures, orbit it, download a PNG.
OBJ To STL
Convert an OBJ model to STL for your slicer, scaled to millimetres.
STL To GLB
Convert STL to GLB in the browser with colour and up-axis fixed.