Lights Out

Every press flips a light and its four neighbours. Switch the whole grid off in as few presses as you can.

Presses0

Lit0

Solvable in0

Grid

Level

Best: –

How to play

Tap a cell to toggle it together with the cells above, below, left and right of it. The aim is a grid with no lit cells.

Every puzzle is built by pressing cells on a dark grid, so it can always be solved. The order of your presses never matters, and pressing a cell twice undoes it.

The "solvable in" number is the fewest presses that will do it. Match it for a perfect solve. A hint marks one cell that belongs to the shortest solution.

Worth knowing

Chase the lights: work down row by row, pressing the cell directly below each lit cell. That clears everything but the last row.

What is left in the last row tells you which cells in the top row to press. Then chase the lights down once more and the grid goes dark.