Convert 123DX to STL Online — Free & Fast | AnyConv

123DX to STL Converter

Quickly convert multiple 123dx files to stl — free & online.

Drag & drop your files here or click to upload

How to convert 123DX to STL online

Follow these simple steps to convert 123dx files to stl using AnyConv. It works on all devices — Windows, Mac, Linux, iPhone, Android.

Upload your 123DX file

Drag & drop your file into the upload area. You can also click to select it manually. Max file size: 100 MB.

Start converting

Hit the “Convert” button to turn your 123DX into STL. The process usually takes just a few seconds.

Download your STL

Once ready, download your converted file instantly. The download link is private and only works on your device.

What is a 123DX file?

123DX is a proprietary 3D model format used by Autodesk's now-discontinued 123D Design software. It allowed users to create and save 3D designs, including models for printing or further editing in more advanced CAD tools.

Although the software has been retired, 123DX files can still be opened using Autodesk Fusion 360 or converted into other formats like STL or STEP for continued use in 3D modeling workflows.

How to open 123DX files

123DX files were originally created using Autodesk 123D Design. Although the software has been discontinued, they can still be opened with Autodesk Fusion 360 after importing or converting the file.

You can also use AnyConv to convert 123DX to STL or STEP for use in other 3D modeling tools.

Key facts about 123DX

  • Full name: Autodesk 123D Design Model
  • Extension: .123dx
  • MIME type: application/octet-stream
  • Developed by: Autodesk
  • Initial release: 2012

Useful links and resources

What is a STL file?

STL (Stereolithography) is one of the most common 3D file formats used for 3D printing. It describes the surface geometry of a 3D object without including color, texture, or other attributes.

STL files are supported by virtually all 3D printers and modeling software. They are lightweight and easy to process, making them the go-to choice for rapid prototyping and additive manufacturing.

How to open STL files

STL files can be opened in most 3D modeling and slicing programs such as Blender, Cura, TinkerCAD, and Fusion 360. They are essential for 3D printing workflows.

Use AnyConv to convert STL files to formats like OBJ or STEP for further editing or integration with CAD systems.

Key facts about STL

  • Full name: Stereolithography File
  • Extension: .stl
  • MIME type: model/stl
  • Developed by: 3D Systems
  • Initial release: 1987

Useful links and resources

Convert from 123DX

Need to change your 123DX files to a different format? Below are all the available tools to help you turn 123DX into the format you need.

❓ Frequently Asked Questions

Answers to common questions about converting 123DX to STL
  • Do I need to register to convert 123DX files?
    Not at all! You can convert 123DX to STL without signing up or installing anything.
  • Is it safe to convert 123DX to STL on AnyConv?
    Absolutely. All 123DX and STL files are securely handled and automatically deleted after 1 hour. Nobody can access your data.
  • Will the quality change after converting 123DX to STL?
    We do our best to preserve the original quality during 123DX to STL conversion. The result is accurate and clean.
  • How long does it take to convert 123DX to STL?
    Most conversions from 123DX to STL take just a few seconds — even for larger files.
  • Can I upload more than one 123DX file?
    Yes, batch conversion is supported. You can convert multiple 123DX files to STL at once — fast and easy.
  • What browsers support 123DX to STL conversion?
    All modern browsers! Chrome, Firefox, Safari, Edge — AnyConv runs online and supports converting 123DX to STL on any platform.