Convert OBJ to STEP you can actually edit
Upload a watertight OBJ and get back a solid STEP file built from real surfaces — smooth NURBS patches for scans and organic shapes, true planes and cylinders for mechanical parts. Preview it in 3D for free; pay only when you download.
Drop a file, or click to choose
Supports .stp / .step / .stlConversion complete Free
How OBJ to STEP conversion works here
A OBJ file is just triangles. A STEP file is supposed to describe surfaces. Most free converters bridge that gap by writing every triangle as its own tiny planar face, which produces a STEP file that is huge, slow to open and impossible to fillet, offset or select in CAD.
Vertessia rebuilds the geometry instead. For scans, teeth, sculpts and other free-form shapes it lays a quad layout over the mesh and fits a B-spline (NURBS) patch to each quad. For parts that started life in CAD it detects planar and cylindrical regions and replaces them with exact analytic surfaces. The result is a closed solid you can cut, measure and design around. OBJ files are converted to a clean triangle mesh first; materials are ignored.
Upload your OBJ
The mesh must be watertight — closed, with no holes. We check this in a couple of seconds and tell you straight away if it needs repair.
Choose the surface type
Organic / scanned for NURBS patches (with an adjustable patch size), Mechanical for planes and cylinders. A typical run takes 30 seconds to 2 minutes.
Preview, then download
Inspect the rebuilt model in the 3D viewer for free. Downloading the STEP costs one credit; new accounts get three free downloads.
Questions about OBJ to STEP
Is this OBJ to STEP converter free?
Conversion and the full-quality 3D preview are free. Downloading the STEP file costs one credit (from $1 per file in a pack), and every new account gets 3 free downloads. If a conversion fails you are not charged.
Will the STEP be editable in SolidWorks, Fusion 360 or FreeCAD?
Yes — it opens as a solid body made of real surfaces, so you can section it, offset it, add features to it and take measurements from faces. It does not recreate a parametric feature tree (sketches, extrudes, fillets as features); no mesh-to-CAD tool can do that automatically.
Why does my mesh have to be watertight?
A solid needs a closed boundary. If the mesh has holes or open edges the result would be an open shell rather than a solid, so we check first and stop early instead of charging you for a file you can't use. Repair the mesh in your scan software, Meshmixer or Blender and upload again.
How large a OBJ can I upload?
Up to 100 MB per file. Very dense scans convert faster, and give a lighter STEP, if you decimate them to a few hundred thousand triangles first — the rebuilt surfaces smooth over the triangle detail anyway.
What happens to my file?
It is processed on our own servers in Canada and is never shared or sold. You can opt out of us keeping a copy for quality improvement with the checkbox under the upload box.
Free to convert and preview. Pay only for the STEP you keep.
Mesh conversions and STEP → mesh are free, forever, without an account. Reconstruction (mesh → editable STEP) always runs at full quality and the 3D preview is free — one download costs one credit. Failed conversions and re-downloads are never charged.
- All mesh conversions, unlimited
- STEP → mesh, unlimited
- Unlimited reconstruction previews
- 3 free STEP downloads when you sign up
- Or 30 downloads for $30
- Credits never expire
- No subscription
- Small “Converted by Vertessia” note in the STEP header — geometry untouched
- 30 STEP downloads / month
- Clean STEP header
- Priority queue
- 200 STEP downloads / month
- Clean STEP header
- Priority queue
Higher volume? Team — 1,000 downloads / month for $249 — subscribe. API usage draws on the same credits. On-premise licensing for medical, defence and manufacturing: info@vertessia.com