If you work in engineering, architecture, or design, chances are you've had to deal with CAD files at some point. Viewing these files can be a hassle if you don't have access to the right software. Fortunately, there are several free online CAD viewers that allow you to open, view, and even annotate CAD files without needing to install any software.

Here are 5 of the best free online CAD viewers available:

1. AutoCAD web app

AutoCAD, the popular CAD software, offers a free web app that allows you to view and edit DWG files online. You can access it from any browser and even make basic edits to your drawings.

2. A360 Viewer

A360 Viewer is a free online tool from Autodesk that supports over 50 file formats, including DWG, DWF, RVT, and more. It allows you to view 2D and 3D CAD files with ease.

3. Onshape

Onshape is a cloud-based CAD platform that offers a free plan with online CAD viewing capabilities. You can upload your CAD files to Onshape and view them from any device with an internet connection.

4. SketchUp Free

SketchUp Free is a web-based version of the popular 3D modeling software, SketchUp. It allows you to view and edit 3D models online, making it a great option for viewing CAD files in 3D.

5. DWG FastView

DWG FastView is a lightweight and fast CAD viewer that supports DWG, DXF, and DWF file formats. It allows you to view, measure, and mark up CAD files online without any cost.

These free online CAD viewers offer a convenient way to view and collaborate on CAD files without the need for expensive software. Whether you're a professional engineer or a hobbyist designer, these tools can help you access and work with CAD files easily.

In conclusion, there are plenty of options for free online CAD viewers that provide the basic viewing and editing capabilities you need without breaking the bank. Whether you work with 2D or 3D CAD files, there's a free online CAD viewer out there that can meet your needs.