Open-source 2D floor planning : OpenCalque (free, MIT, Windows/macOS/Linux/web)
I wanted to draw the plan of an apartment to scale and print it. The options were a CAD program with a 1990s command line, or a subscription. So I started building the tool I wanted.
OpenCalque is a 2D editor for floor plans and layouts with a Figma-style interface. "Calque" is French for tracing paper. Try it right now, nothing to install: https://opencalque.com
What it does today:
- Walls that behave like walls. They join at any angle, stay joined when you drag one, and doors and windows snap in and cut the opening.
- Rooms find themselves. Click inside closed walls and you get a named room with its area, which follows the walls when they move.
- Trace an existing plan. Drop a PDF or a photo, click two points you know the distance between, draw over it.
- DXF in and out, plus SVG.
- A component library (furniture, kitchen, bathroom, electrical symbols) and extensions that are data, not code, so installing one can't run anything.
- Optional AI assistant that edits the drawing from a description, with Claude, a local model through Ollama, or any OpenAI-compatible API. Nothing goes online unless you use it.
- English, French, Spanish, German.
The part I care most about: a drawing is plain JSON with a published schema, and every edit is a small JSON operation. The editor, the CLI and the assistant all use the same operations, so you can generate or modify a plan from a script.
No account, no telemetry, MIT licence.
- Repo and screenshots: https://github.com/laurent512/opencalque
- Downloads: https://github.com/laurent512/opencalque/releases/latest
I'd love feedback from people who draw plans for real: what would stop you from using this, and what's the first thing you'd miss?