A prototype redstone simulator with a 3D viewer. Each design below is a list of blocks; the simulator runs it tick by tick and a bench test checks whether it works. Flip the lever or press the button to watch it run.
Click any part in the 3D view, or pick one here, to see what it does.
What the simulator covers. It's a port of Minecraft Java Edition 26.3's redstone rules: block updates in the game's order, scheduled ticks with priorities, piston events, quasi-connectivity, torch burnout and slime/honey pistons. Blocks: levers, buttons, dust, torches, repeaters, comparators, observers, pistons, dispensers, lamps, glass, slabs, slime, honey and obsidian. Not yet: hoppers, droppers and other item blocks, rails, entities, and Bedrock Edition. It has been checked against known in-game behaviour, but it's a prototype: test anything important in the game.