Free online SCAD to OBJ converter

What the SCAD format is

SCAD is the source-code format used by OpenSCAD, a constructive solid geometry application for creating precise 3D models with scripted primitives, transformations, Boolean operations, modules, and variables. A SCAD file contains instructions rather than a stored polygon mesh, so its visible geometry is generated when OpenSCAD previews or renders the script.

You commonly encounter SCAD files in parametric CAD projects, 3D-printing repositories, configurable mechanical parts, and projects that use include or use statements to load libraries. The main file may therefore depend on additional SCAD files, fonts, or data files.

What the OBJ format is

OBJ is a text-based polygon-mesh format supported by Blender, Maya, 3ds Max, Unity, Godot, CAD utilities, and many 3D viewers. It stores vertices, texture coordinates, normals, and polygon faces; an accompanying MTL file can describe basic materials, while image textures remain separate files.

OBJ is useful when the recipient needs an editable or viewable mesh rather than the original OpenSCAD script. It preserves the model's surface geometry after tessellation, but it does not preserve SCAD parameters, Boolean history, modules, variables, or procedural editability.

How to actually convert SCAD to OBJ

Using OpenSCAD and Blender

1. Open the main .scad file in OpenSCAD and verify that all referenced files are available.
2. Render the final solid with Design → Render (CGAL), or press F6. Preview-only geometry from F5 may not represent the final Boolean result.
3. Export an intermediate mesh with File → Export → Export as STL. Save it as model.stl. From a terminal, the equivalent command is openscad -o model.stl model.scad.
4. Open Blender and choose File → Import → STL, then select model.stl.
5. Select the imported object and check its dimensions. Apply the intended scale with Object → Apply → Scale if the mesh has the correct physical size but an unapplied transform.
6. Export the mesh through File → Export → Wavefront (.obj). Enable selection-only export if the scene contains unrelated objects, and save model.obj. Keep the generated .mtl file with the OBJ if materials are needed.

OpenSCAD normally does not provide direct OBJ export, so the STL intermediate is the standard desktop workflow. FreeCAD can also import the STL and export an OBJ, but Blender provides more control over cleanup, normals, scale, and object structure.

Using the online converter

For an online conversion without installing software, 101convert.com can convert the file for free when the SCAD-to-OBJ option is available: upload the SCAD file, choose OBJ as the output, start the conversion, and download the result. Online processing may fail when the script references missing libraries or local files, and private designs should not be uploaded unless the service's handling terms are acceptable.

Quality, compatibility, and limitations

The STL export resolution controls the quality of the eventual OBJ. In OpenSCAD, increase $fn for circles and curved surfaces, or adjust $fa and $fs; lower values create visibly faceted OBJ geometry, while very high values increase file size and conversion time. These variables must be set before the CGAL render and STL export.

SCAD models are generally exported as single-color geometry through STL. The OBJ conversion therefore cannot recover original SCAD colors, materials, textures, or object labels. If separate parts are required, export them as separate solids or assign separate objects during the Blender stage.

Check scale after import because STL has no universally enforced unit declaration. OpenSCAD commonly treats one coordinate unit as one millimeter, while some OBJ applications interpret coordinates differently. Inspect dimensions in Blender and set the scene units or export scale before delivering the file.

Non-manifold edges, self-intersections, zero-thickness surfaces, and failed Boolean operations can produce missing faces or invalid OBJ meshes. Repair the geometry in OpenSCAD first, then render again; Blender's Mesh → Clean Up tools can remove some duplicate or degenerate geometry after import.