Open Source Flowchart Software

The Excel to Graphviz Relationship Visualizer spreadsheet transforms your Excel data into professional Graphviz diagrams. Enter simple "A is related to B" rows to instantly generate polished relationship graphs using the Graphviz DOT language. Ideal for data analysis, network visualization, and IT architecture. Free, open-source, MIT-licensed. Customize the look of nodes, edges, and clusters with the Style Designer. Build a CSS-like gallery of reusable styles that lets you apply consistent visual themes. Run SQL queries for advanced data import. Export graphs as BMP, GIF, JPG, PDF, PNG, or SVG files (with animation support). View Graphviz DOT code and command-line messages. Works on Windows and macOS with a ribbon interface and UTF-8 support for global text. Explore illustrated guides at https://exceltographviz.com With over 10,000 downloads and a SourceForge Community Choice award, this open-source VBA tool clarifies complex data. Download now and turn data into insight.

ioDraw is a free online drawing software, which is used to make flow chart, mind map, Gantt chart, whiteboard, mermaid, poster, and more—no registration required. It also features AI-generated charts.