.123D File

.123d is Autodesk 123D Drawing

Key Features: .123D File Extension

Features	Description
File Extension	.123d
Format	Binary
Created by	Autodesk
Category	CAD

What is an .123D file?

CAD drawing created by 123D, a free 3D CAD design application provided by Autodesk; may contain multiple parts that together comprise the model; can be published to standard raster image formats or to Autodesk's .DWG format.

123D is often used for prototyping since it is not as robust as AutoCAD. Therefore, models are often used for showcasing ideas as mesh models, props, and scenery. Many free 123D models are provided at the 123D website for download.

NOTE: 123D was discontinued in March 2017.

Autodesk

CAD

Binary

How to solve problems with 123D files

Associate the 123D file extension with the correct application. On :
Windows: Right click on any 123D file and then click "Open with" > "Choose another app". Now select another program and check the box "Always use this app to open *.123D files". Mac: Right click (or Ctrl-click) the 123D 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 .123D is Autodesk 123D Drawing. Because only the current version supports the latest 123D file format. Search, therefore, e.g. on the Autodesk manufacturer website after an available .123D is Autodesk 123D Drawing update.
To make sure that your 123D file is not corrupted or virus-infected, get the file again and scan it with antivirus software.