10 Best Free ERD Tools in 2026 — Tested and Compared

Best for: designing MySQL or PostgreSQL schemas from scratch — completely free

1. SQL Designer — sql-designer.com

SQL Designer is a browser-based schema design tool built specifically for MySQL and PostgreSQL. The workflow is visual: drag tables onto a canvas, add columns with real database types (INT, VARCHAR, DECIMAL, TIMESTAMP), set PRIMARY KEY, UNIQUE, NOT NULL, and AUTO_INCREMENT or SERIAL constraints with toggles, and draw foreign key relationships by connecting columns. The diagram uses crow's foot notation. When the schema is ready, export a complete CREATE TABLE DDL script for MySQL or PostgreSQL in one click — or paste existing SQL to visualise it instantly.

The free tier has no table cap, no diagram limit, and no paywall on SQL export. Collaboration features — shareable links, embeddable iframes, and real-time multiplayer editing — are included at no cost. No credit card required; the demo canvas works without an account.

Limitations: only MySQL and PostgreSQL are supported — no SQLite, SQL Server, Oracle, or other engines. There is no reverse-engineering from a live database connection; you import SQL scripts, not live databases. The tool is focused on schema design, not query execution or database administration.

Verdict: the strongest free option for visual MySQL and PostgreSQL schema design from a blank canvas, with no meaningful free-tier restrictions. Narrower database support than some competitors.

Best for: teams who want visual design with broader database support

2. DrawSQL — drawsql.app

DrawSQL is a polished visual database schema designer with a clean drag-and-drop interface. It supports MySQL, PostgreSQL, SQLite, and SQL Server, and produces SQL export for all of them. Data types, constraints, and foreign key relationships are all handled visually. The interface is arguably more refined than most competitors. Team collaboration — sharing, commenting, and multiple editors — is built in.

Limitations: the free tier caps diagrams at approximately 15 tables. For small schemas this is fine; for larger projects it becomes a hard boundary. Some advanced collaboration features are paywalled. Paid plans start at $15/month.

Verdict: an excellent visual ERD tool with broader database support and a more polished UI than SQL Designer; the table cap on the free tier is the main constraint.

Best for: developers who prefer defining schemas in code rather than clicking

3. dbdiagram.io

dbdiagram.io is text-first: you write your schema in DBML (Database Markup Language) and it renders a visual diagram on the right. It's fast and efficient for developers who can type a schema directly. The rendered diagrams are clean and shareable. It's probably the most widely-used tool in this list.

Limitations: SQL export is behind a paywall on the free tier — you can draw and share, but you cannot generate MySQL or PostgreSQL DDL without paying. Diagrams are public by default; private diagrams require a paid plan ($9/month). Real-time collaboration is paywalled. For non-developers or visual thinkers, the DBML-first approach adds friction.

Verdict: the go-to for code-first teams who want fast schema documentation; the SQL export paywall makes it a poor fit as a free end-to-end design tool.

Best for: conceptual data models and communication diagrams, not working schemas

4. draw.io / diagrams.net

draw.io is a free, open-source, general-purpose diagramming tool with a large shape library that includes entity and table shapes. It's completely free with no document limits. Diagrams save to your local filesystem, Google Drive, GitHub, or OneDrive. There is both a browser version and a desktop application.

Limitations: no SQL awareness whatsoever. Column types are plain text labels — the tool does not validate them or understand what they mean. There are no constraint concepts, no structural foreign key relationships, and no SQL export. You can draw something that looks like a schema, but you cannot generate DDL from it. For communicating a rough data model to non-technical stakeholders, it works well. For designing a database that needs to produce runnable SQL, it is the wrong tool.

Verdict: excellent free tool for visual communication; not suitable for database schema design that needs to produce SQL.

Best for: documenting and understanding existing databases with AI assistance

5. ChartDB — chartdb.io

ChartDB is an open-source tool designed primarily around importing and visualising existing database schemas. Paste a SQL script or connect to a live database, and ChartDB generates a visual diagram with AI-assisted explanations of the schema. It supports MySQL, PostgreSQL, SQLite, SQL Server, and others. It is MIT-licensed and self-hostable — no cloud dependency if you host it yourself. DDL export is included.

Limitations: oriented toward documentation and understanding rather than greenfield design. Building a schema from scratch is less polished than DrawSQL or SQL Designer. The AI features require an API key or the cloud version. Self-hosting requires running your own server. Cloud plans start at $12.5/month.

Verdict: the strongest option for teams who need to understand, document, or reverse-engineer an existing schema with AI assistance. Less suited to design-first workflows.

Best for: students, academics, and anyone learning ERD notation

6. ERDPlus — erdplus.com

ERDPlus is a free, browser-based ERD tool aimed squarely at academic use. It supports standard Chen notation, crow's foot notation, and relational schemas. There are no account limits. It can generate SQL for simple schemas. The interface is minimal and approachable for first-time users learning entity-relationship concepts.

Limitations: the UI is basic compared to modern tools. SQL generation is limited and not production-ready. There is no collaboration or sharing beyond exporting images. It has not been updated frequently. It is a teaching tool, not a professional one.

Verdict: ideal for learning ERD concepts in an academic setting; not the right tool for real production database design.

Best for: rapidly sketching a small schema before writing any code

7. QuickDBD — quickdatabasediagrams.com

QuickDBD is a text-to-diagram tool: type a schema definition in a simple syntax and it renders a clean visual diagram on the right. It exports SQL for MySQL, PostgreSQL, SQL Server, and others. The tool is fast for small schemas — fewer clicks, faster iteration. It is browser-based with no install required.

Limitations: the free plan is limited to one diagram only. Multiple diagrams require a paid plan ($14/month). There is no drag-and-drop visual editing — the interface is text-driven. For users who prefer clicking over typing, this is the wrong workflow. The one-diagram limit makes it impractical for real projects with multiple schemas.

Verdict: good for a quick one-off schema sketch; the single-diagram free limit rules it out for ongoing use without paying.

Best for: teams who need polished presentation diagrams with collaboration

8. Lucidchart

Lucidchart is a general-purpose diagramming platform with strong collaboration features — comments, version history, integrations with Slack, Jira, Confluence, and Google Workspace. It has ERD-specific shapes and templates. The user interface is polished. It is used broadly in enterprise environments for all types of diagrams.

Limitations: like draw.io, Lucidchart has no SQL awareness — column types are text labels, there is no constraint system, and there is no DDL export. The free tier limits diagrams to 60 objects. Paid plans start at $8/user/month. For actual database schema design that produces SQL, Lucidchart is the wrong tool.

Verdict: excellent for presentation-quality diagrams and collaboration in existing workflows; not suitable for schema design that needs to generate SQL.

Best for: teams who need multi-database visual design with a wider engine list

9. DB Designer — dbdesigner.net

DB Designer is a visual database schema designer that supports MySQL, PostgreSQL, SQLite, and SQL Server with a drag-and-drop canvas, data type dropdowns, constraint toggles, and foreign key relationship lines. It is a closer direct competitor to SQL Designer than most other tools in this list, but with broader database engine support.

Limitations: the free tier limits the number of objects per diagram (approximately 50). Collaboration and sharing are more restricted on the free plan. The interface feels dated compared to newer tools like DrawSQL. The object cap is reached quickly on real-world schemas. Paid plans start at $19/month.

Verdict: a solid visual ERD tool with wider database engine support than SQL Designer; the free tier object cap is the main practical friction.

Best for: generating ERDs automatically from a live database you already run

10. DBeaver — dbeaver.io

DBeaver is a full-featured desktop database client that connects to a live database, runs queries, manages data, and administrates the server. One of its features is automatic ERD generation: connect to PostgreSQL, MySQL, SQLite, Oracle, or virtually any other database, and DBeaver generates a visual entity-relationship diagram from the live schema. The Community Edition is completely free and open-source.

Limitations: requires download and installation — not browser-based. It is not a design-first tool; the ERD is generated from an existing database, not built visually. It is a large application — overkill if you just need to draw a diagram. Enterprise features cost $29/user/month.

Verdict: the best tool for visualising and working with an existing live database from the desktop; not the right choice for designing a new schema from scratch or for browser-based use.