STL to STEP Assistant

Convert STL, GLB, and OBJ models to STEP offline and privately.

STL to STEP Assistant is a focused local 3D model tool for converting mesh-based models into STEP files for CAD workflows.

Open STL, STLB, GLB, 3MF, USDZ, OBJ, 3DM, FBX, DAE, PLY, 3DS, AMF, DRC, KMZ, MPD, WRL, and other model files, preview them in a clean 3D scene, choose a conversion quality mode, then export and save the current main model as a STEP file. You can also load and view STEP and STP files to inspect conversion results.

Built for mesh-to-STEP work

• Convert STL, including binary STLB, to STEP
• Convert OBJ, GLB, GLTF, 3MF, 3DM (Rhino), FBX, DAE, PLY, USDZ, 3DS, AMF (additive manufacturing), DRC (Draco), KMZ (zipped 3D scene), MPD (multi-part LDraw), and WRL (VRML) model formats to STEP
• Load and view STEP files to inspect conversion results
• Export STEP with BRep reconstruction, useful for turning some engineering mesh models into easier-to-edit CAD surfaces
• Preview 3D models and BRep reconstruction results before export
• Export the current main model, not the whole scene or other objects
• Keep floor, lights, camera, and visual effects out of the STEP file
• Process files on device, so model data stays on your device
• Privacy focused, with no account, no login, no ads, no tracking, and no data collection

Choose STEP export geometry and quality as needed

• BRep: tries to convert suitable mesh models into easier-to-edit CAD surfaces, useful for some engineering parts and regular geometry
• Faceted Small: fast, lightweight STEP export for everyday use
• Faceted Balanced: balance detail and file size
• Faceted High: preserve more model detail
• Faceted Original: export as directly from the source mesh as possible

Understand the result before saving

• View source file information
• Review mesh, triangle, and vertex counts
• Check triangle reduction by quality mode
• Get a simple export risk hint
• See the final STEP file size after conversion

It is made for makers, engineers, designers, 3D printing users, CAD users, and anyone who needs to convert mesh models into STEP exchange files.

Pricing & Access

• Free: Open, preview, inspect models, load STEP files, and use Small STEP export.
• CAD Surface Export unlocks BRep STEP export for suitable models, helping produce easier-to-edit CAD surface results.
• In-App Purchase unlocks: Permanently unlock CAD Surface Export, Balanced, High, Original, and other STEP export capabilities. No subscription required.
• Payment is charged to your App Store account.
• Purchases can be managed through your App Store account settings.

Privacy & Purchase Terms

• Privacy Policy: https://h53d.github.io/s2s/policy.html
• Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

Have questions or need support? Reach out to danjian42@gmail.com.