Backend is not connected

The server may not be running. Run cd backend && python app.py in a terminal, then refresh this page.

Refresh
Mold

Free STL Mold Generator

Upload an STL file and create a mold with alignment pins, a pouring sprue, and air vents.

📤
Upload your model
Drag and drop an STL file or choose one from your computer
Advanced Settings

Tune the setup preview before generating the final STL. Empty fields use automatic sizing.

Changes update the setup preview live once an STL is loaded. After generation, only the final mold preview is shown.

📐
No model loaded
Upload an STL file from the left panel
Setup Preview

Create Printable Two-Part Molds From STL Files

Mold is a free online mold generator that turns your STL model into a printable two-part mold. Upload an STL file, tune the wall thickness, tolerance, alignment pins, pouring sprue and air vents, then generate the final mold STL. The tool is designed for resin casting workflows where a clean split mold and controlled pour channel are important. It is ideal for makers, sculptors and small product prototypes that need a fast path from 3D model to reusable casting mold.