Generate an ER Diagram for your database, free.

The simplest, fastest online tool for creating an ER Diagram (ERD) for your existing database. Generate yours in seconds.

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Lightening fast to set up

It takes seconds to map and visualise your database schema. Connect your database directly - Trevor will then derive all the relationships between your tables using foreign keys and common naming conventions.

Easy to share and export

You can share your ERD with your team online by inviting them to Trevor. You can also print a copy.

Explore and query the data itself

If you want to dig into the data itself, you can create and run queries against your database using SQL or Trevor's point and click interface.

Works with large databases

In addition to color-coding your tables, you can limit your ER Diagram to subsets of related tables, making it easy to work with large data sets.

Creating your online ER diagram

How does it work?

Trevor uses foreign keys and common naming conventions to derive the relationships between your database tables and create and maintain an ERD. You can make changes / modifications manually to correct existing or add new relationships.

Can I invite my team?

Yes, you can invite your team using their company, Google, or Heroku accounts.

Will the diagram change as my schema changes?

Yes, it's based on your live data.

How does Trevor connect to my database?

Learn more about how Trevor connects to your database, including our security policies, here.

What databases are supported?

We currently support MySQL, PostgreSQL, and Amazon Redshift.

My database is massive. Can Trevor handle it?

Yes! In some cases, you may wish to manually optimise the diagram by dragging certain tables to new locations.

Have another question?

Ping us via the blue Intercom button, we'd be happy to help :)