As Visio is Microsoft's commercial solution for professional diagramming and workflow drafting, it has many alternatives just like other parts of the Microsoft Office Suite. These alternatives share many of the features found in Visio, such as support for scalable vector graphics files so that your charts and diagrams don't suffer any loss in quality when resized.
PathVisio is a free open-source pathway analysis and drawing software that allows drawing, editing and analysing biological pathways. It provides a basic set of features for pathway drawing, analysis and visualization. Additional features as plugins.
Ardoq helps organizations navigate their digital transformation journey with the most flexible, data-driven, and forward-thinking tool in the Enterprise Architecture industry. Predict, plan, and execute change across the organization.
Creates diagrams from textual descriptions! It provides a unified API with support for BlockDiag, BPMN, Bytefield, C4 (with PlantUML), Ditaa, Erd, GraphViz, Mermaid, Nomnoml, PlantUML, SvgBob, UMLet, Vega, Vega-Lite, WaveDrom.