Are you in need of a free STP file viewer to open and view 3D CAD models? Whether you're a professional engineer, designer, or hobbyist, having the right software to view and analyze STP files is essential. Fortunately, there are several free STP file viewer options available that offer powerful features without breaking the bank. Here are the 4 best free STP file viewer software for 2021:

1. FreeCAD: FreeCAD is an open-source parametric 3D CAD modeler that comes with built-in support for STP files. It offers a comprehensive set of features for modeling, rendering, and simulation, making it an ideal choice for users looking for a versatile STP file viewer.

2. eDrawings Viewer: Developed by SOLIDWORKS, eDrawings Viewer is a free software that allows users to view, print, and review 3D models and 2D drawings in a compact format. It supports viewing STP files along with a wide range of other CAD file formats, making it a versatile solution for designers and engineers.

3. Autodesk Fusion 360: While Fusion 360 is known for its powerful CAD and CAM capabilities, it also offers a free version for personal use, which includes the ability to view 3D models, including STP files. With its cloud-based collaboration features, Fusion 360 is an excellent choice for users who need to share and collaborate on 3D designs.

4. A360 Viewer: A360 Viewer is a web-based tool by Autodesk that allows users to view 3D CAD models in the browser without the need for any additional software. It supports STP and various other CAD file formats, and its simple, user-friendly interface makes it a convenient choice for quick model viewing and sharing.

These free STP file viewer options provide a range of features to meet the needs of designers, engineers, and enthusiasts. Whether you're looking for a standalone desktop application or a cloud-based solution for collaboration, there's a free STP file viewer out there that can fulfill your requirements without costing a cent.