ERD Viewer Online

The ERD Viewer Online analyzes and visualizes relational schemas from multiple input formats (SQL DDL, JSON Schema, YAML, or manual definitions). It builds an internal model of entities, attributes, primary/foreign keys, and relationships, then renders a readable diagram. The tool focuses on domain logic and data-model quality, enabling professionals to inspect and communicate complex structures without writing code. A layout engine arranges entities to minimize overlap and emphasize connectivity, while notations and key indicators help convey cardinality and constraints. Exports provide diagram fidelity for documentation and implementation workflows. This is particularly valuable for database designers, data architects, software engineers, and educators who need quick, repeatable visual representations of data models. Unique value comes from multi-format input, solid validation, and reliable exports that support engineering workflows.

The tool emphasizes accuracy of relationships and keys, supports forward and reverse engineering directions, and maintains an auditable model suitable for design reviews and implementation planning.