Astah Viewer

Astah Viewer enables quick access to Astah models in a browser without installing the full editor. It targets software engineers, system architects, educators, and students who review UML, ER, and SysML diagrams during design reviews, onboarding, or audit tasks.
Workflow starts with a file upload or drag-and-drop of supported Astah formats: .asta, .uml exports, or XMI snapshots. The tool renders each diagram as a crisp, scalable canvas with pan and zoom, plus a thumbnail diagram list for navigation.
Under the hood, a domain parser ingests the model, builds a graph of elements and relationships, and a deterministic layout engine assigns coordinates to nodes. The renderer produces SVG or PNG outputs, with options to export selected diagrams for documentation.
This enables faster reviews, improved collaboration, and repeatable visuals for stakeholder reports. The viewer is read-only and privacy-conscious, processing files in-session, with no edits to source models.
Designed for teams that need quick, shareable visuals of complex architectures, the tool supports multiple diagram types and preserves layout stability across reloads, making it suitable for design reviews, classroom demonstrations, and consultant handoffs.