The File Extensions Database

.123C File Extension

  • Developer by: Autodesk
  • Category: CAD Files
  • Format: Binary

What is an .123C file?

.123C is Autodesk 123C Drawing

CAD model created by 123D, a free 3D CAD drawing program developed by Autodesk; can include multiple parts that make up the overall model; used for drafting and prototyping mesh models, props, and scenery.

123C files are similar to the .123D format, which is the default format used by Autodesk 123D. Both file types are similar to .DWG files and can be published to the DWG format.

NOTE: Many free 123C models are provided for download at the 123D website.

How to solve problems with 123C files

  • Associate the 123C file extension with the correct application. On :
    Windows: Right click on any 123C file and then click "Open with" > "Choose another app". Now select another program and check the box "Always use this app to open *.123C files". Mac: Right click (or Ctrl-click) the 123C file, then click "Open with" > "Other...". Then choose another program and check the "Always Open With" box. Linux: Right click on the file, and select "Open with" and choose another program. iPhone: Tap the file. If you do not see an app to open the file, then tap Share "Share" and choose an app. Alternatively, save the file. Then open the Files app Files app. There long-press on the file, then release your finger. You will see a black menu bar. Then tap "Share" and select an app. Android: Tap the Settings icon on your smartphone, then tap on the Apps section. There tap the Options icon in the top right-hand corner of the screen to change the default apps.
  • Update your software that should actually open .123C is Autodesk 123C Drawing. Because only the current version supports the latest 123C file format. Search, therefore, e.g. on the Autodesk manufacturer website after an available .123C is Autodesk 123C Drawing update.
  • To make sure that your 123C file is not corrupted or virus-infected, get the file again and scan it with antivirus software.