This article explains what 123D Autodesk was, why it disappeared, how you can still (potentially) run it on macOS, and—most importantly—the best modern alternatives for Mac users in 2025 and beyond.
Autodesk 123D was a suite of free, entry-level 3D modeling and design tools designed for hobbyists and makers. While it was once a staple for Mac users, Autodesk . 123d Autodesk For Mac
Free, native macOS