Lights Out — free online logic game
Switch every light off — but each tap flips its neighbours too.
About Lights Out
Lights Out is a classic toggle puzzle. Tapping a light flips it and its four neighbours; the goal is to turn every light off. This version calculates the true minimum number of moves for every board using linear algebra, so you can aim for a perfect solve.
Your best score, XP and achievements are saved in this browser only. Switch to Daily challenge in the game bar to play today’s shared puzzle.
How to play Lights Out
- 1Tap a tile to flip it and the tiles above, below, left and right.
- 2Turn every light off to win.
- 3Fewer moves earn more points; matching the minimum is a perfect score.
- 4Use Undo if a move goes wrong.
Controls: Tap or click tiles. Keyboard: arrow keys move, Space toggles.
Tips and strategy
- Work row by row: clear the top row, then fix the rest from below.
- Tapping the same tile twice cancels out — never repeat a tile.
- The order of taps does not matter, only which tiles you tap.
Lights Out FAQ
Can every board be solved?
Yes — each board is created by tapping a few tiles from a blank board, so it can be reversed.
How is the minimum moves number found?
With Gaussian elimination over GF(2), the same maths that proves which Lights Out boards are solvable.
Does order matter?
No. Only the set of tiles you tap matters, not the order.