Free ER diagram tool?

Looking for a free er diagram tool? There are many of them on the market and Moon Modeler belongs among them as well.
The free tool can be used for visual definition of smaller database structures for both relational database systems, e.g. MariaDB, PostgreSQL, SQLite and NoSQL databases, e.g. MongoDB or object-document mappers like Mongoose.

Moon modeler can be installed as a trial version that automatically switches to freeware mode after the trial version expires.

Example of a sample ER diagram created for MariaDB target platform:

Trial version

All key features are enabled in the trial version and you can try fully functional software for 14 days. Then the software expires and the following modal form is displayed:

As you can see, you can purchase a commercial version by clicking the Buy Now button and following instructions, activate already purchased product or continue with the freeware version of the ER diagram tool.

Click Continue with freeware to enable the freeware mode.

Limitations of the free ER diagram tool

In freeware mode, you can create smaller projects with 10 objects at maximum. You can add more objects to your project, but saving the project will not be allowed.
Note: Freeware mode can also be used as a viewer for existing projects.

When you add more than 10 objects to a project or try to save a larger project (opened from the file system, for example), the following notification appears in the software:

#free er diagram tool