•4 min read•CAD
Verdict:For free parametric CAD we could export with, FreeCAD first; OpenSCAD for scripted parts; Blender for mesh/STL; LibreCAD for 2D DXF. None open SketchUp .skp natively.
| Tool | Price | Platforms | Best for | Tested |
|---|---|---|---|---|
| FreeCAD | Free (open source) | Linux, Windows, macOS | Free parametric solids, STEP/STL export, mechanical-style CAD | Yes |
| OpenSCAD | Free (open source, GPL) | Linux, Windows, macOS | Free scripted parametric parts for printing and machine components | Yes |
| Blender | Free (open source, GPL) | Windows, macOS, Linux | Free mesh modeling and STL when CAD history is secondary | Yes |
| LibreCAD | Free (open source, GPLv2) | Linux, Windows, macOS | Free 2D drafting and DXF floor plans/profiles | Docs only |
Last updated October 18, 2026
Short answer by use case: for free parametric 3D CAD, start with FreeCAD (we exported STEP and STL). For scripted parts / 3D printing, use OpenSCAD (STL + preview PNG). For mesh modeling and visualization, Blender (STL). For 2D DXF plans, LibreCAD (installed; headless PDF hung—docs-backed). Trimble’s own SketchUp Free is web-based per plans and pricing—useful for concepts, not a Linux offline CAD stack.
How we ordered the tools: tools we exported with hands-on (FreeCAD, OpenSCAD, Blender) come first; LibreCAD is last because our headless test did not finish. None of these products is ours.
Deeper SketchUp exit notes: SketchUp alternatives.
Mechanical parts with editable parameters. FreeCAD.
Code-defined brackets and printable widgets. OpenSCAD.
Organic mesh, rendering, game-ready props. Blender (see also SketchUp vs Blender when that page ships).
2D floor plans / profiles. LibreCAD or export DXF from FreeCAD workbenches when appropriate.
Still happy in a browser with Trimble. SketchUp Free web plan—confirm limits on Trimble’s pricing page. AutoCAD comparisons belong on SketchUp vs AutoCAD.
What we saw: FreeCAD 1.0.0 (freecadcmd) built a 100×50×30 mm box and wrote STEP (~6.8 KB) and STL (~0.7 KB) successfully. Downloads page listed newer stable builds when checked; we ran Debian’s 1.0.0.
Lacks vs SketchUp: steeper learning curve; push-pull UX differs; no native .skp.
Get it: freecad.org/downloads.php.
What we saw: OpenSCAD 2021.01 compiled a matching .scad box to STL and a PNG preview.
Lacks: no interactive push-pull modeling—everything is code (or generated code).
Get it: openscad.org/downloads.html (GPL per about page).
What we saw: Blender 4.3.2 exported a matching mesh STL. Upstream listed 5.2.2 LTS on related checks; Debian gave 4.3.2.
Lacks: not parametric CAD history like FreeCAD; different mental model from SketchUp.
Get it: blender.org/download.
Installed LibreCAD 2.2.0.2; dxf2pdf on a four-line DXF rectangle did not finish within 45 seconds under xvfb, so tested: false. Site: librecad.org.
.skp to open in FreeCAD/OpenSCAD/Blender.People search “cad software free” for three different outcomes. 2D CAD means dimensions on a plane (floor plans, profiles)—LibreCAD’s DXF world. Parametric 3D CAD means solids with a history tree you can revise—FreeCAD. Mesh modeling means vertices and faces for visualization or printing—Blender (and many SketchUp habits). OpenSCAD sits beside FreeCAD as parametric-by-code. If you pick Blender expecting AutoCAD command-line drafting, you will bounce; if you pick LibreCAD expecting SketchUp push-pull massing, you will bounce harder.
Our FreeCAD run wrote both STEP (exchange with other CAD/CAM) and STL (mesh for many printers). OpenSCAD wrote STL plus a PNG preview from the same dimensions. Blender wrote STL from a mesh cube matching the size. Those formats are the practical migration currency when .skp will not open. File sizes on our test machine were tiny for a primitive box; production assemblies will be larger—do not treat our byte counts as performance claims.
FreeCAD documents architecture-oriented workbenches on its site, but we only smoke-tested a solid export. That is not evidence of Revit/IFC parity. LibreCAD covers 2D plans. If your firm’s deliverable is BIM coordination, expect a larger process change than “install FreeCAD.” Trimble’s paid SketchUp tiers and other commercial BIM tools remain in that conversation—see SketchUp alternatives and our SketchUp comparison pages.
FreeCAD 1.0.0, OpenSCAD 2021.01, Blender 4.3.2, LibreCAD 2.2.0.2 on Debian 13 CPU-only. Primitive 100×50×30 mm box: FreeCAD → STEP+STL; OpenSCAD → STL+PNG; Blender → STL. LibreCAD dxf2pdf hung >45 s under xvfb → not marked as tested. No SketchUp binary on the test machine—migration advice assumes rebuilds.
For 3D printing, the two paths we verified are OpenSCAD (a scripted part compiled to STL with a PNG preview) and FreeCAD (STL plus STEP for exchange). Blender also wrote an STL from a mesh. Our primitive test box only proves the exporters run—check manifold status in your slicer before you print. Blender also doubles as a free motion-graphics tool; see our After Effects alternatives if you animate as well.
Debian 13 CPU-only. Kept in our test logs: the FreeCAD, OpenSCAD and Blender scripts, the four-line DXF, and the STEP, STL and PNG outputs, plus recorded package versions.
Our 100×50×30 mm box proves exporters run; it does not prove printer-ready meshes. Check STL manifold status in your slicer, confirm FreeCAD unit preferences match your drawing, and treat OpenSCAD $fn tessellation as a quality knob. SketchUp users moving to FreeCAD should expect to re-learn constraints instead of push-pull improvisation.
Trimble’s Free plan keeps you in a browser with Trimble’s constraints—confirm current limits on the plans page. Offline FreeCAD/OpenSCAD/Blender matter when you need air-gapped machines, Linux labs, or scripted part libraries. They are not “the same as SketchUp Free with more buttons”; they are different modelling philosophies. Choose based on whether your deliverable is a concept massing, a STEP for machining, or an STL for a printer.
No SketchUp install. LibreCAD dxf2pdf hung under xvfb—no PDF evidence. No GPU, no architecture-scale BIM/IFC round-trips.
FreeCAD 1.0.0, OpenSCAD 2021.01 and Blender 4.3.2 were run on CPU-only Debian 13: FreeCAD exported a 100×50×30 mm box to STEP and STL via freecadcmd; OpenSCAD compiled matching dimensions from a .scad script to STL and PNG; Blender exported a matching mesh STL. LibreCAD 2.2.0.2 was installed; dxf2pdf under xvfb did not finish within 45 seconds, so LibreCAD stays docs-backed. SketchUp pricing from Trimble plans page on 2026-10-14.