From thought to diagram in seconds — entirely offline.
A fast, local-first drawing and diagramming app. Sketch ideas, map out systems, and create diagrams — all without accounts, cloud sync, or network requests. Your data stays on your machine.
Get the latest build for your platform from GitHub Releases:
Full docs are available at ipcrm.github.io/napkin.
- Simple shape library including geometric primitives, connectors, sticky notes, freehand drawing, and text
- Hand-drawn sketch style powered by rough.js
- Connectors that bind to shapes and stay attached when you move them
- Direct, elbow, and curved line routing
- Multiple tabs for organizing diagrams
- Export to PNG, SVG, and
.napkin(JSON) files - Keyboard shortcuts for every tool
- Grid snapping and alignment guides
- Fully offline — no accounts, no cloud, no tracking
Napkin includes a built-in Model Context Protocol (MCP) server that lets AI agents create and manipulate diagrams programmatically. Enable it from the settings menu, then point your AI client at http://127.0.0.1:21420/mcp.
See the MCP documentation for setup instructions and the full tool reference.
Want to build from source or contribute? See the Contributing Guide.