Hamstertransfer is offline-first client proofing software that runs entirely in modern web browsers as a standalone HTML file, requiring no installation, databases, or servers. The drag-and-drop canvas allows image placement, resizing, zooming, and alignment with grid snapping. Users can customize typography, add styled text blocks, adjust background colors, and replace logos with PNG or SVG files. PDF export creates print-ready documents, while HTML export compiles projects into lightweight, shareable files. Exported files open in a clean gallery interface, letting clients arrange, zoom, and mark preferred images, which are compiled for email updates. Images and layout data are embedded directly into HTML files, removing the need for third-party platforms. Built with HTML, CSS, and JavaScript, Hamstertransfer integrates into websites via iframe embedding without plugins or server-side scripts.