MS 3D Viewer is a popular tool for viewing and interacting with 3D models, but many users are unsure about what file format it supports. MS 3D Viewer primarily uses the .obj file format to open and display 3D models. The .obj format is a widely used file type for representing 3D geometry, and it is compatible with a variety of 3D modeling software and applications. In addition to .obj files, MS 3D Viewer also supports other common 3D file formats such as .stl and .fbx. These file formats allow users to import and view their 3D models with ease. Whether you're a professional designer, a hobbyist, or simply curious about 3D modeling, MS 3D Viewer provides a user-friendly interface for exploring and interacting with 3D content. With its support for popular file formats, MS 3D Viewer is a versatile tool for anyone interested in 3D modeling and visualization.