easyeda/online-gencad-viewer

Online GenCAD Viewer is a browser-based tool for opening and inspecting PCB (printed circuit board) design files in the GenCAD format (.cad extension). PCB files describe the physical layout of an electronic circuit board, where components are placed, how copper traces connect them, and where holes and solder pads go. This viewer lets you see all of that visually without needing specialized design software installed. You open a .cad file by dragging it onto the page or using a file picker. The board then renders in your browser with multiple layers, top and bottom copper, inner layers, silkscreen (the printed labels), drill holes, and the board outline, each of which you can show or hide independently. You can search the component or net list (a "net" is an electrical connection between points), click on a component to highlight it and jump to its location on the board, zoom with the scroll wheel, and pan by dragging. The tool is built in TypeScript and compiles to a single self-contained HTML file, meaning you can download that file and use it offline with no server or installation required. The rendering engine is LeaferJS, which uses the HTML5 Canvas element to draw the board graphics. The interface supports both Chinese and English. This is made by EasyEDA, an online PCB design platform, and is useful for engineers, hobbyists, or procurement teams who need to inspect or share a PCB layout without opening a full CAD application.