How to convert STEP to GLB
- Drop your .step file into the box above, or click Choose file.
- Check the 3D preview, size and triangle count.
- Make sure GLB is selected as the output format. Adjust scale or up-axis if needed.
- Click Download. The .glb file is created instantly on your device.
Why convert STEP to GLB?
GLB is the best way to show a CAD part on a website or in AR. Colours from the STEP file are kept as materials, and the model is converted from millimetres to metres automatically.
What changes in the conversion
- Surfaces become triangles. STEP stores exact curved surfaces; GLB stores a triangle mesh. Curves are approximated with a fine tolerance.
- Up-axis. STEP is usually Z-up while GLB is Y-up; the model is rotated so it stands the right way up. Untick "Convert up-axis" to keep the raw coordinates.
- Geometry is preserved. Every triangle, with all object transforms applied, ends up in the new file.
STEP vs GLB
| STEP | GLB | |
|---|---|---|
| Full name | ISO 10303 (STEP AP203/AP214/AP242) | binary glTF |
| Stores | exact solids, assemblies and part names | geometry, materials, textures, hierarchy and animations |
| Colour | Yes | Yes |
| Textures | No | Yes |
| Units | stored in the file (usually millimetres) | metres by specification |
| Exact CAD geometry | Yes | No |
About the formats
STEP (ISO 10303 (STEP AP203/AP214/AP242)) was standardised as ISO 10303 for exchanging engineering data between CAD systems. It describes exact solid geometry (B-rep surfaces, edges and assemblies) rather than triangles. It is the neutral CAD format used by SolidWorks, Fusion 360, Inventor, CATIA, FreeCAD and Onshape.
GLB (binary glTF) was defined by the Khronos Group as the single-file binary form of glTF 2.0. It packs meshes, PBR materials, textures, scene hierarchy and animations into one compact file. It is the standard for 3D on the web, AR viewers, e-commerce product views and game engines.
Frequently asked questions
Is this converter free?
Yes. You can convert STEP to GLB for free – up to 3 conversions a day, with no sign-up and no watermark. If you need more, Pro gives you unlimited conversions and batch conversion (free for 7 days).
Are my files uploaded to a server?
No. The conversion runs entirely in your browser using WebAssembly and JavaScript. Your model never leaves your computer, which also makes it safe for confidential parts and patient data.
Is there a file size limit?
There is no fixed limit. Files of a few hundred megabytes work on a typical laptop; the practical limit is your device's memory.