If you work with 3D CAD models, you may come across STP files, which are commonly used for storing 3D data. To open and view STP files, you'll need a dedicated STP file viewer. Fortunately, there are several free tools available that make it easy to access and visualize STP files without any cost. Whether you're a professional engineer or a hobbyist creator, having the right STP file viewer at your disposal can save you time and effort. Here are some top free STP file viewers that you can try:

1. FreeCAD: FreeCAD is an open-source 3D CAD modeler that comes with built-in support for opening and viewing STP files. It offers a user-friendly interface and a wide range of features for working with 3D models.

2. eDrawings Viewer: eDrawings Viewer is a free tool from SolidWorks that enables users to open and view STP files as well as other 3D file formats. It provides a simple and intuitive way to visualize 3D models with various viewing options.

3. 3D-Tool Free Viewer: 3D-Tool Free Viewer is another great option for opening and inspecting STP files. It supports a variety of 3D file formats and allows users to perform measurements, sections, and annotations on the 3D models.

4. Autodesk Viewer: Autodesk Viewer is a web-based tool that allows users to upload and view 3D models, including STP files, directly in the browser. It offers collaboration features and support for multiple file formats, making it a versatile option for viewing 3D data.

5. STP Viewer: STP Viewer is a simple and straightforward tool specifically designed for opening and viewing STP files. It provides basic viewing capabilities and is suitable for users who need a no-frills solution for accessing STP files.

These free STP file viewers offer a range of features and capabilities for opening and viewing STP files without any cost. Whether you're looking for advanced visualization options or just need a basic tool for quick access to STP files, there's a free STP file viewer out there to suit your needs.