Convert FBX to STEP through STL
There is no direct upload for FBX to STEP. Convert the FBX file to STL in your browser, then upload the STL to STL to STEP, which rebuilds it as a faceted solid.
Before you convert: what this keeps and what it destroys
Preserved
- The shape, as planar faces built from the triangles
- Overall dimensions and proportions
- Watertightness, where the input is watertight
- The unit, recorded in the file
- Supported base or vertex colours
- Separate parts and their positions
Destroyed
- Cones, spheres, tori and NURBS, rebuilt as planar facets
- Animation, rigs, cameras and lights, if the file has them
- Texture images and texture coordinates, if present
Why people convert FBX to STEP
Somebody has sent you a game or visualisation asset and asked for something manufacturable. The right answer is usually to go back and ask for STEP, because an FBX means the sender has given you a visual asset rather than a model of a part.
If that is not available, this produces a faceted B-rep: planar faces from coplanar triangles, shared edges, and a closed shell if the input was closed. It opens in CAD and it works as reference to model around. There are no exact surfaces in an FBX to recover, so there is no feature tree and no cylinder that is genuinely a cylinder.
Rigs, animation, cameras and lights are not read at all, which for this destination costs you nothing, since STEP could not have held them.
What you get
You get a plain-text STEP file you can open in an editor containing a boundary representation: planar faces, shared edges and, where the input was closed, a closed shell that CAD software will treat as a solid. Triangles that lay in the same plane are merged into single faces, so a flat side that arrived as two hundred triangles leaves as one face.
This conversion carries across the unit the file records, supported base or vertex colour and the supported part structure.
This page does not upload anything. The server converts STL to STEP only, and nothing else on this site leaves your computer.
What to check afterwards
- FBX declares its unit in the file. Check the output dimensions in the receiving application, especially when its import settings can override the unit.
- This is a reconstruction, not a recovery. Coplanar triangles are merged into planar faces and the result is a real solid, but cones, spheres, tori and NURBS surfaces are not recovered and there is no feature tree. Use it as reference geometry.
If you need something this conversion cannot give you
If you need a parametric model, use the original CAD file or remodel the part using this output as reference. Surface fitting can create new geometry, but a mesh does not contain the original sketches or feature history.
Going the other way
This site reads FBX but does not write it. For the reverse conversion, use an application that can export FBX.
How we know this conversion works
This pair was checked against 2 files from the test corpus on 2026-09-24. Each run parses its own output back in and compares the bounding box, the triangle count and, for closed solids, the volume against the input.
A pair that fails those checks doesn't get a page. That's why this site lists 120 conversions and not the several hundred a format-times-format grid would suggest.