Which 3D file format should I use?
STL, OBJ, 3MF, STEP, GLB/glTF, PLY, USDZ — they are not interchangeable. Answer two quick questions and get the right one for your job, with the trade-offs spelled out.
● Runs entirely in your browser — no uploads, nothing storedAll formats at a glance
A quick reference for the eight formats this tool recommends between.
| Format | Best for | Color / textures | Animation | CAD precision | Watch out for |
|---|---|---|---|---|---|
| STL .stl | 3D printing (universal) | No | No | No (mesh) | Geometry only — no color, units or settings; large meshes bloat |
| 3MF .3mf | Modern 3D printing | Yes | No | No (mesh) | Some old tools/marketplaces still expect STL |
| OBJ .obj + .mtl | Simple textured meshes | Yes (MTL) | No | No (mesh) | Textures live in separate files; no scene/animation |
| glTF / GLB .glb / .gltf | Web, games, realtime, AR (Android) | Yes (PBR) | Yes | No (mesh) | Delivery format, not for editing or printing |
| USDZ .usdz | Apple AR / Quick Look | Yes (PBR) | Yes | No (mesh) | Apple-centric; hard to author off macOS; pair with GLB |
| STEP .step / .stp | Mechanical CAD exchange | No | No | Yes (B-rep) | Not a mesh — slicers/engines/web can't use it directly |
| PLY .ply | 3D scanning / point clouds | Vertex color | No | No | Capture format; convert before printing or using in engines |
| FBX .fbx | Legacy DCC / Autodesk pipelines | Yes | Yes | No (mesh) | Proprietary; prefer glTF for open delivery |
Frequently asked
STL vs OBJ — which should I use?
Use STL when you only need geometry for 3D printing — every slicer reads it. Use OBJ when you need per-face color or UV texture via an accompanying
.mtl file. Neither carries animation or CAD precision; for those use glTF or STEP.Is 3MF better than STL for 3D printing?
Technically yes — 3MF stores color, multi-material, textures, units and print settings in one compact file, and is supported by Bambu Studio, PrusaSlicer and Cura. But STL is still the most universally accepted format, so keep an STL export for older tools and marketplaces.
What format should I use for the web or three.js?
glTF, specifically the binary
.glb — it bundles meshes, PBR materials, textures and animation into one small file that <model-viewer> and three.js load fast, and compresses further with Draco/Meshopt.Best format for AR on an iPhone?
USDZ for Apple Quick Look on iOS, plus GLB for Android Scene Viewer. Export both from one source — USDZ won't open on Android and GLB won't open in Quick Look.
Which format keeps CAD precision?
STEP (.step/.stp) stores exact B-rep solids — real curves and surfaces, not triangles — so parts stay precise and editable across SolidWorks, Fusion 360 and FreeCAD. Convert to STL/3MF only once geometry is final.
Does this tool upload my files?
No. It asks about your use case only — no file uploads, no server, nothing stored. It runs entirely in your browser.
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