About
sql-designer.com is completely free and open source ERD tool. Current features include:
Graphical designer where you can create, edit and connect tables using drag-and-drop
Import and export to and from sql, txt, and json files
Support for MySQL and Postgres
Multiple diagrams that you can save (unlimited)
Since it's open source, feel free to visit my repository at gitlab.com/Snydi/sql-designer