April 22, 2026
The chart below shows the most popular 3D file formats based on usage data from 3dviewer.net. The data covers a 30-day period and includes 3D models viewed on the website.
STL remains the most popular format, continuing to lead within the 3D printing community. OBJ also ranks highly, despite being a very old format. More modern formats such as glTF and FBX are gaining popularity thanks to their efficiency and support for advanced features.
One notable surprise is the popularity of the STEP format. Although it was developed in the 1990s for CAD data exchange, it is still widely used today. This is likely due to its versatility, as it supports a broad range of applications, including 3D printing, CNC machining, and architectural design. Additionally, 3dviewer.net is one of the few online 3D viewers that supports STEP files, which may contribute to its strong representation in this chart.
March 21, 2026
The 3dviewer.net and 3dconverter.net websites support over 30 different 3D file formats. However, even with this wide range of options, there are still some formats that users wish were supported.
Based on analytics data, the following formats were most frequently uploaded but are not currently supported by the websites:
- DWG: A format used for 2D and 3D design data, commonly associated with AutoCAD.
- SLDPRT: A SolidWorks part file, widely used in mechanical design.
- X_T: A Parasolid model file, often used in CAD applications for 3D modeling.
- MAX: A 3ds Max scene file, used for 3D modeling, animation, and rendering.
- DXF: A drawing exchange format, used for CAD data interoperability.
As this list shows, supporting certain formats is not always feasible. These are proprietary formats with complex structures and limited or no public documentation, which makes it extremely difficult to implement reliable support in an online viewer or converter. Hopefully, open SDKs or better documentation for these formats will become available in the future.
How to convert STEP files in the browser?
February 20, 2026
STEP and IGES are two of the most widely used formats for exchanging 3D CAD data. However, they can be difficult to work with due to their complexity and mathematical precision. Fortunately, there are now online tools that allow you to convert STEP and IGES files directly in your browser, without the need for downloading any software.
The technology that makes this possible is called WebAssembly, which enables developers to compile C++ code into a format that can run in the browser. As a result, complex 3D geometry can be processed and converted client-side, without relying on server-side processing. This helps to keep your files private and secure.
To support this, the widely used Open Cascade library has been compiled to WebAssembly, bringing STEP and IGES compatibility to online converters. This allows users to easily convert their CAD models into more widely supported formats like STL or OBJ, making it easier to share and use designs across different platforms and applications.