Open-source alternatives to Lucidchart
The open-source or self-hostable project you can use instead of Lucidchart, with license, free-edition limits and setup checked against official sources.
- diagrams.net (draw.io) — diagrams.net draws flowcharts and technical diagrams in the browser or on the desktop, so it can replace Lucidchart for diagramming. This is a replacement use, not an official claim by the project.