diagram2codeAbout Diagram2Code
We build developer tools that eliminate the gap between design and implementation — starting with our diagram to code converter for database schema generation from ER diagrams.
Our Mission
Diagram2Code exists to make database schema design faster and less error-prone. Every developer who has hand-written SQL from an ER diagram knows the pain — typos in column names, mismatched foreign keys, forgotten constraints. We eliminate that friction.
We believe the diagram is the source of truth. Your schema, ORM models, and database migrations should all flow from the same visual representation, not drift apart over time. Diagram2Code keeps them in sync.
Our diagram to code approach means you design once in Mermaid or PlantUML and generate correct SQL or ORM code instantly — no hand-editing, no drift. Whether you call it diagram 2 code or diagram-to-code, the goal is the same: let the diagram drive the implementation.
What We Built
Diagram2Code is a full-stack tool that accepts Mermaid ER and PlantUML entity-relationship diagrams and generates production-ready output. It ships as a web UI, and a REST API.
SQL DDL Generation
Generates CREATE TABLE statements, primary keys, foreign keys, indexes, constraints, and dialect-specific type mappings for PostgreSQL, MySQL, SQLite, and Oracle 19c+.
ORM Model Generation
Produces ready-to-use model code for GORM, SQLAlchemy, TypeORM, Prisma, JPA/Hibernate, Django ORM, Sequelize, and Entity Framework Core.
REST API
Every feature is available via a documented REST API, enabling integration into CI/CD pipelines, code generators, and IDEs. Premium tiers unlock higher quotas and protected endpoints.
Live Preview
The web UI renders your Mermaid ER diagram visually as you type, so you can spot errors in your diagram before converting — no round-trip to the server required.
Technology Stack
Diagram2Code is built with a lean, production-focused stack. The backend is written in Go for performance and low resource consumption; the frontend is vanilla HTML, CSS, and JavaScript with zero framework dependencies.
🧭 What We Stand For
Free Core, Always
The core SQL generation features will always be free. We run a sustainable freemium model, not a bait-and-switch paywall.
Privacy First
We do not store the diagrams you convert. Your schema data is processed in memory and never persisted on our servers.
Developer Experience
Every decision — from API design to error messages — is made with developer ergonomics as the top priority.
Correctness Over Features
We'd rather support fewer databases with correct output than many databases with subtle bugs. Golden-file tests cover every code path.
Sustainable Growth
We grow at a pace that keeps quality high. Every new feature ships with tests, documentation, and a migration path.
Where We're Going
We're actively working on code generation from class diagrams — generate full project scaffolds (REST controllers, services, repositories) from a UML class diagram. We're also exploring bulk conversion, ZIP downloads, and deeper IDE integrations.
Want to follow along or contribute? Check out our documentation, star us on GitHub, or get in touch.
Ready to try it?
Paste your first ER diagram and have production-ready SQL in seconds — no sign-up required.