A high-performance, infinite canvas for brainstorming, teaching, and system design. This diagram maker free online is built for speed and privacy.
Space + Drag: Pan CanvasMouse Wheel: Zoom In/OutDel: Delete Selected ObjectV: Select Tool | H: Hand ToolS: Sticky Note | T: Text ToolIs it really private? Yes, this is a private flowchart maker. All data stays in your browser's memory and is never sent to our servers.
Can I export for presentations? Yes, you can export your diagram maker work as high-quality PNG, SVG, or PDF files.
What is Mermaid.js? It's a tool that allows you to create diagrams using a simple markdown-like syntax. It's the best way to do text to diagram creation.
Don’t take our word for it. Open your browser’s DevTools (F12 → Network tab), then run this tool on any image. You’ll see no upload request at all — your file never leaves this tab. You can even turn off Wi‑Fi once the page has loaded and keep working. Every tool on this site works the same way — all processing happens on your device.