About Light Switch
Light Switch starts with some lights on across a 5×5 board. Pressing a square switches it and its neighbours above, below, left and right. Turn every light off. Each board is made from a dark board by real presses, so it can always be cleared, and par shows the fewest presses that will do it.
How to play Light Switch
- Pressing a square switches it and the squares directly above, below, left and right of it.
- Lights that were on go off, and lights that were off come on. Turn every light off.
- Par is the fewest presses that can clear today’s board. Pressing a square twice cancels it out.
- Fewest presses wins, then the fastest time.
Tips & strategy
- Order does not matter: the same set of presses always gives the same board.
- Pressing a square twice cancels out, so in the best answer every square is pressed once or not at all.
- Try chasing the lights down: press under each lit square in a row, then deal with the bottom row.
- Undo takes back a press, so you can explore without worrying.
- Corner and edge squares have fewer neighbours, so pressing them changes fewer lights.
Light Switch: questions and answers
What is par?
Par is the fewest presses that can clear today’s board, worked out exactly when the puzzle is made.
Can every board be cleared?
Yes. Each board is made from a dark board by pressing squares, so pressing the same squares again clears it.
How is Light Switch ranked?
Fewest presses first, then the fastest time.
Do undone presses count?
No. Undo removes your last press from the count, so only the presses still on the board when you finish are counted.