Create flowcharts, sequence diagrams, class diagrams, and more using Mermaid syntax. Live preview with one-click copy and export.
Diagramm Editor is a free online design tool that works right in your browser — whatever you enter is processed locally and never sent to a server.
No installation, no signup; works on both phone and desktop, ready to use instantly.
We noticed most online tools upload your files to remote servers. Since privacy is our core principle, we built this tool to process everything locally in your browser.
Ja, völlig kostenlos und ohne Anmeldung.
Ja, es funktioniert auf mobilen Browsern mit Touch-Unterstützung.
Design
Yes. Diagramm Editor is a pure front-end tool: whatever you type or paste is processed only in your browser's memory and never sent to a server. It disappears as soon as you refresh or close the page.
Privacy & Security: All processing happens locally in your browser. Files are never uploaded or stored.
Privacy: All processing happens locally in your browser. Your files and data never leave your device — no upload, no server, no tracking.