Speakers can play uploaded audio when powered. Buzzers generate a tone directly in the browser.
Presets
Presets clear the board and load a ready circuit.
Controls
Drag parts from the bottom drawer. Left-drag parts to move. Right-drag empty space to pan. Mouse wheel zooms. On mobile, use browser pinch zoom if needed. Select a part and press E to edit. Select a switch/button and press Space to toggle. Hold W, then left-click and drag from one blue terminal to another to place a wire. Circuits only power when there is a closed path from battery + back to battery -. Click wires to select, Delete removes.