3D file formats compared: 3DM, GLB, STL, OBJ, FBX and more
Rhino's 3DM is the only common format here that keeps exact curves, its units and named layers together, which is why jewellery is designed in it. GLB is a mesh made for the web and AR, with materials and separate parts in one file. STL is a bare mesh for printing, with no units, parts or materials. OBJ, FBX, Collada and PLY sit in between.
3D Jewelry Designer1 min read
3D formats compared
| Format | Exact curves | Units recorded | Separate parts | Materials | Used for |
|---|---|---|---|---|---|
| Rhino 3DM .3dm | Yes | Yes | Yes, with layers | Yes | Jewellery CAD |
| GLB .glb | No, mesh | Metres by definition | Yes | Yes, PBR | Web, AR, product pages |
| STL .stl | No, mesh | No | Usually one mesh | No | 3D printing, casting resin |
| OBJ .obj | No, mesh | No | Yes, groups | In a separate .mtl | Moving a mesh between programs |
| FBX .fbx | No, mesh | Yes, a unit scale | Yes | Yes | Animation and game pipelines |
| Collada .dae | No, mesh | Yes, a unit scale | Yes | Yes | Older interchange, SketchUp |
| PLY .ply | No, mesh | No | Usually one mesh | Vertex colours | 3D scans |
Each format links to a free viewer that opens it in your browser.
Reading the table
The first question for any file is whether it holds exact curves or a mesh. Exact curves, as in a .3dm, are what you design and edit in. Meshes are what you print, render and put on the web, and every mesh format is an approximation of the design at some level of detail.
The next two decide whether a file is useful beyond its shape: whether it records its units, so it can be measured and weighed, and whether it keeps separate parts, so metal and stones can take their own materials.
Opening any of them
Every format in the table links to a free viewer that opens it in your browser and lists what is inside, so you can check a file before sending it on.
Questions
Which format should I send to a caster or printer?
Usually STL, because printers and casting software expect a closed mesh. Check the units with them first, since an STL does not record whether it was drawn in millimetres or inches.
Which format should go on a product page?
GLB. It is one compact file with its materials and separate parts, so a web viewer can load it in a single request and let shoppers switch metals.
What is the difference between exact curves and a mesh?
Exact curves describe a surface mathematically, so it stays smooth at any zoom. A mesh approximates it with flat triangles, and a coarse one shows facets on curved surfaces.
Related
- 3DM viewer: open a Rhino file online
Open a Rhino .3dm file in your browser, rendered as jewellery, with every part, its layer and whether it is metal or stone listed. No Rhino needed.
- OBJ viewer: open an OBJ file online
Open an .obj mesh in your browser, rendered with jewellery materials, with each of its groups listed as a part. Free and nothing is uploaded.
- STL viewer: open an STL file online
Open an .stl mesh in your browser, rendered as jewellery rather than flat grey, with its parts listed. Free, nothing to install, nothing uploaded.