Quick start

1. Drag parts from the left palette onto the canvas (or click a part, then click the canvas). Parts snap to a 20px grid.
2. Wire pins: click a pin dot, then click the target pin. Wires route orthogonally. Click a wire to start a junction.
3. Move parts by dragging. Press R (or the Rotate button) to rotate, Del to delete, Ctrl+Z / Ctrl+Y for undo/redo.
4. Pan with Space + drag, middle-mouse drag, or two fingers. Zoom with the mouse wheel or pinch (0.4x – 3x).
5. Press Run to simulate. Click a switch while running to open/close it. LEDs burn out above 30mA!
6. Save circuits in the browser, export/import JSON files, or use Share link to store the circuit in the URL.
7. Boards: the Arduino UNO provides 5V/3.3V/GND pins, the ESP32 provides 3V3/GND — wire them like a battery.