OpenFlowKit

OpenFlowKit is a 100% free, open-source diagram engine built for engineers, architects, and product teams who need clear, professional visuals without paying for costly tools or wrestling with rigid templates.

You can create architecture diagrams and flowcharts in two ways: through a visual drag-and-drop interface, or via 'Diagram as Code' using Mermaid.js and a type-safe DSL. Whether you prefer clicking or coding, your workflow stays smooth and your diagrams stay precise.

Powered by React Flow, OpenFlowKit offers a local-first experience where your data stays on your own machine. There is no signup and no cloud synchronization required, so you can start diagramming instantly and keep sensitive designs fully private.

It also includes Flowpilot, an AI assistant for chat-based diagram editing that helps you adjust complex layouts through simple conversation. On top of that, a unique Figma export delivers fully editable vector shapes, making design handoff effortless.