Open Source BSD Flowchart Software

Wireflow is an open-source collaborative tool for designing and visualizing user experience flows and wireframes directly in the browser, aimed at UX designers, product managers, and developers who need to map out interactive user journeys without heavy graphic design tools. Unlike static flowchart apps, Wireflow’s interface focuses on quick and intuitive creation of flow diagrams that represent screens and transitions, helping teams prototype and iterate on navigation logic and interaction sequences. It supports real-time collaboration, meaning multiple people can work on the same flow simultaneously, making it useful for distributed teams and remote workshops. Users can drag and drop nodes, connect steps with directed lines, and annotate interactions, producing a visual blueprint for app behavior, website navigation, or feature flows.

Free Java Flowchart simulator / interpreter

JLink lets users author flow charts based on ISO 5807 and IBM standards. Developers can use JLink to add flowcharts to applications, serve a flow chart over the web in PDF or PNG, or dynamically create a flowchart with Javascript, Python or Ruby scripts

Aqueduct is a simple state machine library written in Java. Some programs can be described naturally as a state machine or a flowchart; this library is intended to simplify the development of such programs.

Dgrm is a lightweight JavaScript library designed for creating interactive diagrams and visual representations directly within web applications. It provides developers with tools to build flowcharts, graphs, and structured visual layouts using a flexible and extensible API. The library focuses on simplicity, allowing users to define nodes, edges, and relationships without requiring complex setup or dependencies. It supports dynamic updates, enabling diagrams to respond to user interactions or data changes in real time. The system is particularly useful for applications that require visual modeling, such as workflow editors, architecture diagrams, or educational tools. Its modular design allows customization of rendering and behavior, making it adaptable to various use cases. Overall, DgrmJS offers a practical solution for embedding diagramming capabilities into modern web interfaces.

FC Designer is a standalone flowchart designer written in Java.