Which free ER diagram tool should you use? The answer depends on whether you need to sketch entities visually, write a schema as code, reverse engineer a database, or collaborate on a private model. This guide compares the ten tools in the original article by their actual free access and practical limits. A free account, a limited plan, and a temporary trial are different things, so check the current plan before putting a real project into any service.
Jump to: ERD example · tool comparison · all ten tools · FAQs. The original screenshots are retained for reference; interfaces and plan details may have changed since they were captured.
Start with a small, testable ER diagram
For a simple shop, create four entities: Customers (customer_id), Orders (order_id, customer_id), Products (product_id), and OrderItems (order_id, product_id, quantity). Mark each primary key and connect Orders.customer_id to Customers.customer_id. One customer can have many orders. Each order can have many order items, and each product can appear in many order items. OrderItems resolves the many-to-many relationship between Orders and Products.
- List the things the database stores, then turn them into entities.
- Add only the attributes needed to identify records and demonstrate the relationship.
- Mark primary keys (PK) and foreign keys (FK) explicitly.
- Label each relationship with its cardinality, such as one-to-many.
- Check the diagram against a sample order. Can one order contain two different products without duplicating the customer record?
This small example reveals whether a tool supports the notation and level of detail you need. For production work, also check export, privacy, collaboration and whether the model can be kept in sync with your database schema.
Quick comparison: free access and the main trade-off
| Tool | Best fit | Free access to check |
|---|---|---|
| GitMind | Visual ERD sketches and sharing | Limited free plan; verify file and export limits |
| Gliffy | Confluence documentation | Trial and paid plans; sharing permissions may require payment |
| Visual Paradigm Online | Visual ERDs for personal use | Free edition is non-commercial; export conditions vary by plan |
| diagrams.net | Local or chosen cloud storage | Free web and desktop diagramming |
| Lucidchart | Visual collaboration and templates | Free plan limits editable documents and shapes |
| SqlDBM | Enterprise data modeling | Contact vendor about access and pricing |
| dbdiagram | Database schema as text | Free plan with diagram and collaboration limits |
| QuickDBD | Fast keyboard-first sketching | Free Basic plan is limited to a small project |
| Creately | Mixed diagrams and team whiteboards | Free plan limits shapes and export options |
| ERDPlus | ER modeling and learning | Site currently describes all core features as free |
Ten ER diagram tools, with realistic use cases
1. GitMind: sketch an ERD visually
GitMind offers a visual canvas for placing entity boxes and connecting them. It suits an early model that needs review from non-developers. Add the four entities from the example, make PK and FK labels visible, and use distinct connectors for each relationship. The original article called it “completely free” and assumed password-protected sharing; instead, check the current plan for file, export and sharing permissions before using those features.
2. Gliffy: keep diagrams with Confluence pages
Gliffy is currently positioned around technical diagrams in Confluence. It can make sense when the schema explanation belongs beside team documentation. Its sharing help says some sharing features require a paid account, so do not treat a trial as a permanent free collaboration plan.
3. Visual Paradigm Online: ERD drawing for personal projects
Visual Paradigm Online has a free ERD editor for personal, non-commercial use. The pricing page identifies commercial rights and watermark-free exports as paid benefits. That matters if your diagram will go into client work or public documentation. The original claim that every free export is watermark-free is no longer a safe promise.
4. diagrams.net: choose where the file lives
diagrams.net (formerly draw.io) lets you start in a browser and choose local or supported cloud storage. It is a strong choice if you want a file your team can keep in its own repository or Drive. Draw the example with entity shapes and label the one-to-many connectors; agree on notation before different people edit it.
5. Lucidchart: a limited free visual plan
Lucidchart offers a free tier for small diagrams and a separate premium trial. Its official plan information lists three editable Lucidchart documents and 60 shapes per document in the free tier. Check the exact import, reverse-engineering and export features on your plan; the original article presented advanced database connections as if they were universal free features.
6. SqlDBM: evaluate for governed data modeling
SqlDBM focuses on collaborative, governed database models and supported data platforms. Its current pricing page asks teams to contact sales rather than publishing a permanent free-plan allowance. If you need reverse engineering, version control or enterprise review, request the relevant terms before committing a project. Do not infer that a sign-up button means a free ongoing plan.
7. dbdiagram: define the schema with DBML
dbdiagram turns a text schema into a diagram and supports SQL import/export. Its current Free plan lists up to ten diagrams and documentation projects; private mode is now included, while more advanced sharing and collaboration have separate limits. It suits teams that want to review the schema text as carefully as the image.
8. QuickDBD: draft with the keyboard
QuickDBD is also keyboard-first. Its Basic plan currently lists one diagram and ten tables per diagram, so it is well suited to a small prototype such as the four-entity shop example. Verify import, sharing and export on the plan you actually use; the original description treated these as unrestricted.
9. Creately: mixed diagram types and whiteboards
Creately can be useful if an ERD lives alongside process and architecture diagrams. Its Free plan currently limits a diagram to 40 shapes, and the plan table reserves image/PDF/SVG export for paid plans. Try the example first, then check whether the final delivery format fits the free tier.
10. ERDPlus: focus on ER modeling
ERDPlus specializes in entity-relationship diagrams, relational schemas and star schemas. Its site currently describes the core tools, PNG export and SQL generation as free. It is a useful place to practice entities, attributes and cardinality before choosing a larger modeling platform.
Frequently asked questions
Is an ERD the same as a flowchart?
No. A flowchart shows the order of actions and decisions. An ERD shows data entities, their attributes and their relationships. Use a flowchart for “what happens next” and an ERD for “what data connects to what.”
Which free tool should I start with?
For a visual sketch, try GitMind or diagrams.net. For a schema written as text, try dbdiagram or QuickDBD. For learning ER notation, ERDPlus is focused and currently free. Check the plan and storage choice before adding real customer data.
Can a diagram replace database migration scripts?
No. Even if a tool exports SQL, review keys, constraints, data types and migration order in your database workflow. A diagram is a model to communicate and check, not proof that a production change is safe.
Final check: draw the four-entity example, test its one-to-many relationships, then select the tool based on export, privacy and collaboration. The most useful ERD is the one your team can keep accurate as the schema changes.
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