Software Design Editor — Free ERD, Sequence, and FSM Tool
Design software architecture visually. Create ERDs with crow's foot notation, Sequence diagrams, and Finite State Machines (FSM). Export to SQL, Mermaid, XState, or JSON. No install.
What you can build
ER diagrams with crow’s foot and Chen notation — export to SQL CREATE TABLE statements
Sequence diagrams for REST, gRPC, WebSocket, and event-driven call flows
Finite State Machines exported to XState v5 JSON — paste directly into your codebase
UML-style class diagrams with inheritance, association, and dependency edges
Data flow diagrams (DFD) for system architecture documentation
Architecture topology maps with labeled swim lanes and component boundaries
Export formats
SQL — normalized CREATE TABLE with FK constraints from ERD
Mermaid — paste into GitHub Markdown, Notion, or Confluence
XState JSON — run state machines directly in your JavaScript app
SVG — vector export at any resolution, no rasterization
JSON — structured graph export for custom tooling
Frequently asked questions
Can I generate SQL from an ERD I draw here?
Yes. Once you have an ERD with entities and relationships, use the Export → SQL option to generate normalized CREATE TABLE statements with primary and foreign key constraints.
Does the FSM export work with XState v5?
Yes. The JSON export targets XState v5 createMachine() format. You can paste the output directly into your application without modification.
Is this tool free to use offline?
The core drawing engine is MIT-licensed and free. No account is required to draw, export SVG, or export SQL. Advanced features like multi-user collaboration require a GINEXYS Pro plan.