STL ↔ STEP converter

Drop an STL to rebuild it as a STEP solid with real CAD surfaces — planes, cylinders, cones, spheres, tori and free-form faces — or drop a STEP file to see it and download an STL at the accuracy you choose. Everything runs in this browser: the file is never uploaded.

Drop an .stl, .step or .stp file here

Read and converted on this device, in WebAssembly. Nothing is uploaded, nothing is stored, no sign-up.