OBJ to STL converter: the surface, as it is
Drop an .obj and get one .stl file, converted in Blender on our server. The trip keeps the geometry and nothing more; the materials and the textures cannot come along. Free, no account, nothing to install.
How do I convert OBJ to STL?
Drop the file on this page, wait while the server converts it, and download one .stl file.
- 1Choose an .obj, or a zip of the folder that holds it with its textures. Files up to 50 MB.
- 2The converter opens it in Blender on our server and writes STL. Most files take under a minute; the page shows the result in 3D when it is done.
- 3Download one .stl file. The upload and the result are deleted 3 days later.
- In:
- .obj (zipped with .mtl and images)
- Out:
- one .stl file
- Keeps:
- the geometry
- Cost:
- free, no account
- The materials and the textures cannot be carried into STL.
What survives the trip
An OBJ never travels alone: the materials are in a sibling .mtl and the images beside that. Upload a zip of the folder and the materials come through; upload the .obj alone and the mesh arrives grey.
The result is a binary STL of every mesh in the file, merged into one solid, written in the pose the model holds. Materials, textures, bones and shape keys do not exist in STL and are not written.
OBJ and STL do not hold the same things, and the page says so before you upload: the trip keeps the geometry and nothing more, and the materials and the textures cannot come along. STL is what every slicer and every CAD tool reads.
What this conversion cannot do
Measured on real files, not assumed. Everything below is a property of the formats or of the pipeline, and knowing it beforehand is cheaper than discovering it in your 3D tool.
The .mtl and the images have to come along
An .obj carries geometry and texture coordinates and nothing else; the materials live in the .mtl it names, and the images in files the .mtl names. Zip all three together. An .obj on its own converts, but to an untextured mesh.
Converted is not the same as printable
Nothing is repaired, thickened or made watertight. A model built for rendering is a set of open shells, and a slicer will show the holes. That is a modelling job or the repair step in your slicer, not a format conversion.
Uploads stop at 50 MB
A larger file is refused before anything is uploaded. Decimate a dense mesh or shrink the textures in your 3D tool first; neither changes the format.
Frequently asked questions
Why is the result grey?
The .obj was uploaded without its .mtl and images, or the .mtl names images that were not in the zip. Put the .obj, the .mtl and the image files in one zip and upload that.
My model has several parts. Do I get several files?
No, one STL with every mesh in it. Split it in your slicer or 3D tool if you want the parts apart.
Is anything uploaded, and for how long?
Yes: the file you drop goes to our server in New York, is converted there, and both the upload and the result are deleted 3 days after the conversion. Nothing is shared with anyone.
Can I look at the OBJ first?
Yes, without uploading anything: the OBJ viewer draws it in your browser. Open the OBJ viewer →
Can this become a VTuber avatar?
Not as it is: an avatar needs a skeleton, skin weights and a face that moves, and an .obj has none of them. Rig and texture the model in Blender first, then convert the rigged file to VRM.
The other format pairs
All 50 are free, all run the same pipeline, and all say what they drop.
OBJ to GLB
OBJ in, GLB out, free: one file.
STL to GLB
STL in, GLB out, free: one file.
STL to FBX
STL in, FBX out, free: one file.
STL to OBJ
STL in, OBJ out, free: zipped with its files.
GLB to STL
GLB in, STL out, free: one file.
FBX to STL
FBX in, STL out, free: one file.
OBJ to PLY
OBJ in, PLY out, free: one file.
OBJ to DAE
OBJ in, DAE out, free: zipped with its files.
OBJ to USDZ
OBJ in, USDZ out, free: one file.
STL to PLY
STL in, PLY out, free: one file.
STL to DAE
STL in, DAE out, free: zipped with its files.
STL to USDZ
STL in, USDZ out, free: one file.
PLY to STL
PLY in, STL out, free: one file.
DAE to STL
DAE in, STL out, free: one file.
USDZ to STL
USDZ in, STL out, free: one file.
OBJ to 3MF
OBJ in, 3MF out, free: one file.
3MF to STL
3MF in, STL out, free: one file.
STL to 3MF
STL in, 3MF out, free: one file.
GLB to OBJ
GLB in, OBJ out, free: zipped with its files.
FBX to OBJ
FBX in, OBJ out, free: zipped with its files.
PLY to OBJ
PLY in, OBJ out, free: zipped with its files.
DAE to OBJ
DAE in, OBJ out, free: zipped with its files.
USDZ to OBJ
USDZ in, OBJ out, free: zipped with its files.
3MF to OBJ
3MF in, OBJ out, free: zipped with its files.
Only want to look at the file? GLB viewer, FBX viewer and OBJ viewer all run on your own device — nothing is uploaded.
Is your model going into VTubing?
An .obj is a surface without a skeleton, so no converter can make a VRM avatar out of it directly. Rigged and textured in Blender, the same model converts to VRM on the FBX to VRM converter, with the bones mapped onto the VRM humanoid.
Open the VRM converter