Convert COLLADA to STEP through STL
There is no direct upload for COLLADA to STEP. Convert the COLLADA 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 COLLADA to STEP
Usually a SketchUp model that somebody now needs as CAD geometry, and SketchUp is exactly why this deserves a warning.
SketchUp models are built from surfaces and are very often not closed. Internal faces, reversed faces and small gaps are normal in that world and cause nobody any trouble until the moment something tries to treat the model as a solid. This conversion merges coplanar triangles into planar faces and builds a B-rep, and it can only produce a genuine closed solid if what went in was closed. The report tells you whether it was.
COLLADA does declare its unit as a scale factor, so the STEP comes out correctly sized, which is more than can be said for several other routes into this format.
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
- COLLADA 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 COLLADA but does not write it. For the reverse conversion, use an application that can export COLLADA.
How we know this conversion works
This pair was checked against 4 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.