# GLB and glTF for CAD Handoff: A Viewing Mesh, Not the Source

Use GLB or glTF to show a CAD model. Keep STEP when the recipient must measure solids, machine the part or edit the design.

This guide covers general CAD workflows. CADProps supports STEP, IGES, SolidWorks parts and ZIP assemblies, STL, OBJ, 3MF and static GLB/GLTF. Validated conversions are downloadable. Partial assemblies carry warnings; properties cover loaded geometry only.

GLB and glTF are good at showing a model in a browser. They are poor at replacing the engineering file. A supplier who will machine, inspect or revise the part still needs STEP or the native CAD model.

[GLB and glTF](https://www.cadprops.com/guides/glb-vs-gltf-for-cad/index.md) differ mainly in packaging: GLB is one binary file, glTF is a JSON scene that can point at extra buffers and images. Both are static meshes here. Neither is an editable CAD model.

## Send glTF when the task is viewing

Use [STEP to GLB](https://www.cadprops.com/tools/step-to-glb/index.md) or [STEP to glTF](https://www.cadprops.com/tools/step-to-gltf/index.md) when someone needs to rotate the shape, look at components or place the model in a web view. Inspect the result in the [GLB viewer](https://www.cadprops.com/tools/glb-viewer/index.md) or the [glTF viewer](https://www.cadprops.com/tools/gltf-viewer/index.md).

glTF coordinates are in metres. Check one known dimension after conversion. A model that looks right and is 1000 times off in scale is still the wrong deliverable.

A glTF that references `.bin` files or images must include those files. Remote URLs are not loaded. If textures are missing, the geometry may still be present; see [missing glTF textures](https://www.cadprops.com/guides/gltf-missing-textures/index.md).

## Keep STEP when the task is engineering

Choose STEP, not GLB, when the recipient needs any of these:

- a solid volume that is not a mesh estimate
- analytic faces and edges
- a file another CAD or CAM system will import as geometry
- a record of the design that can be compared with the next revision

A GLB made from STEP does not contain the feature tree, tolerances or the original surfaces. [STEP versus a mesh](https://www.cadprops.com/guides/step-vs-stl/index.md) is the same distinction: the mesh is a view of the shape, not the shape definition.

## What not to promise

Do not describe a GLB as the manufacturing master, a lightweight STEP, or a file that can be converted back into the original CAD model. Mesh measurements are approximate. Mass still depends on a density the user chooses, and only after a usable volume exists.

## A practical split

| Recipient needs | Send |
| --- | --- |
| Look at the model in a browser | GLB, or glTF with its local files |
| Machine, quote from solids, or edit the design | STEP, plus the drawing when the drawing controls the part |
| Both | STEP as the engineering file and GLB as the view, from the same revision |

Name the revision on both files. Two attractive views of different revisions are not a handoff.

## Related reading

- [GLB vs glTF for CAD: 3D Model Files, Assets and Units](https://www.cadprops.com/guides/glb-vs-gltf-for-cad/index.md)
- [glTF Missing Textures? Fix .bin and Image File Paths](https://www.cadprops.com/guides/gltf-missing-textures/index.md)
- [Reduce STEP File Size: Keep Required CAD Geometry](https://www.cadprops.com/guides/smaller-step-files/index.md)
- [STEP vs STL: CAD Measurement, Geometry and Accuracy](https://www.cadprops.com/guides/step-vs-stl/index.md)

Original article: https://www.cadprops.com/guides/glb-gltf-for-cad-handoff/

HTML page: https://www.cadprops.com/guides/glb-gltf-for-cad-handoff/