Design Review CAD viewer software lets you view, mark up, print, and track changes to 2D and 3D files for free—without the original design software. Work with a variety of file formats, including: DWF, DWFx, DWG, and DXF (requires installation of free DWG TrueView software); Adobe PDF; as well as image file types such as.bmp, .jpg, .gif, .pcx, .pct, .png, .rlc, .tga, .tif, .mil, .cal, and more.