CADViewer by Orua vs DWGSee

CADViewer by Orua is a free, open-source browser viewer for large engineering drawings and read-only previews. It opens DWG, DXF, STL, STEP/STP, IGES/IGS, and BREP/BRP files through one entry point and toolbar. DWG and DXF files are parsed in a Web Worker with LibreDWG WebAssembly and rendered progressively using Canvas 2D and Path2D. Three-dimensional formats use OpenCascade WebAssembly and WebGL, with selectable metal surface finishes. Controls include pan, wheel zoom, fit-to-view, zoom window, drawing-list visibility, and light or dark backgrounds. Fonts can load on demand, and deployment configuration supports Simplified Chinese and English. The viewer runs on a static web server without an application server or database, with offline or private-network options. Locally selected files stay in browser processing without an account or upload API. It is read-only and lacks editing, property panels, selection workflows, and plugins.

DWGSee is a viewer and editor for DWG, DXF and DWF drawings, with tools to browse, measure, edit and print them. It also supports BMP, JPG, PNG, GIF and TIF images. Editing includes adding drawing objects and changing text, lines, layers and block attributes. Smart-snap tools measure length, angle, radius and area, while printing handles individual drawings or batches. For review, it can show two drawing versions in split windows, synchronize zoom and pan, and highlight differences. Markup can remain in a separate overlay or be added to a DWG as layers, lines and text. The feature list includes encryption and password protection. Pro exports to PDF and raster images; Standard does not include those exports, while copying a drawing into Word as a vector image is listed for Standard and CAD but not Pro. Platforms listed are Android, macOS, web and Windows. Free access and a trial are offered; paid lifetime licenses start at $69, paid once, with one year of free upgrades for Standard and Pro.