ER diagram tool
Model your database with a proper entity-relationship diagram: entities, attributes, keys, and crow's-foot relationships. Generate an ERD from SQL or a schema, or describe it in plain English.
Step by step
Launch Atlas Diagram Studio and choose an ER diagram to start, or paste SQL DDL / a Prisma schema to generate one automatically.
Add tables with columns, mark primary and foreign keys, and connect them with crow's-foot relationships (one-to-many, many-to-many).
Import a schema to skeleton the ERD, or describe the data model in plain English and let AI draft entities and relationships for you.
Review the schema with your team in real time, then export to PNG, SVG, or PDF, or keep the source for your repo.
Why Atlas Diagram Studio
Most online diagram tools are throwaway. This one has an AI engine, real-time collaboration, and lives inside the workspace where the rest of your work already is.
Paste SQL DDL or a Prisma schema and Atlas builds the entities and relationships for you, so documenting an existing database takes seconds, not hours.
Model one-to-one, one-to-many, and many-to-many relationships with proper cardinality, so the diagram is a real design artifact, not just boxes and lines.
The ERD lives inside Atlas alongside the project and technical docs it belongs to, with real-time collaboration and version history.
FAQ
Ready when you are
Atlas Diagram Studio makes every diagram (flowcharts, UML, ERDs, architecture, mind maps) with AI text-to-diagram and real-time collaboration, inside an all-in-one workspace. Start free.