Turn ideas into diagrams with AI

FlowDiagram is a free, browser-based diagram editor for flowcharts, system and integration architecture, data pipelines and entity relationship (ER) database models. Describe what you want to an AI assistant and it writes the diagram; open it here and edit it like anything you drew by hand.

How the AI part works

FlowDiagram publishes a single Markdown skill file at flowdiagram.net/flowdiagram.md. Give it to Claude Code, Codex, Cursor, GitHub Copilot or any assistant that reads project instructions, and from then on "diagram this integration" produces a valid .flow.json document — correct shapes, connectors, tables and vendor logos — plus a link that opens it here in one click.

There is no MCP server to install and keep running, and nothing is uploaded: the assistant writes the file, and the diagram travels inside the link itself. An assistant that cannot read files can still hand over a diagram by writing a URL — see the URL API.

Why FlowDiagram rather than another editor

Built for AI output, not retrofitted. A documented JSON format, a published skill file and a URL API, so an assistant can hand you a finished diagram instead of a description of one.
Nothing leaves your browser. No account, no server storing diagrams, no upload — which matters when a diagram names your internal systems.
It knows your stack. 240+ vendor logos built in, including SAP, Snowflake, AWS, Azure, Databricks and Kafka, so an integration landscape looks like your estate.
Real data modelling. ER diagrams with crow's-foot notation, round-tripping to SQL DDL, Mermaid and DBML — and a live connection to Snowflake.
Free and offline. Every feature, no tiers, no sign-up. It installs as an app and keeps working with no connection.

What you can draw

Flowcharts and process flows, system and integration architecture diagrams, data pipeline and ETL flows, network diagrams, entity relationship models, org and swimlane charts, and freeform sketches. Export any of them as PNG, SVG or PDF, or share a link that carries the whole diagram.

Common starting points include an AI flowchart generator, a system architecture diagram tool, an integration architecture diagram guide, an ER diagram from SQL, a database schema diagram, a Snowflake ER diagram, a SAP integration diagram, a Mermaid editor, a data pipeline diagram builder and a freeform drawing tool — all in the same local-first editor.

JavaScript is required to run the editor itself. With JavaScript turned off you can still read the written documentation:

Documentation — full feature reference, including frequently asked questions and the AI and agent surfaces
Guides — worked examples, including ER diagrams from SQL

Diagramming and drawing software for business and productivity. All third-party logos and trademarks shown in the editor's shape library belong to their respective owners — see trademarks.