What Is This?
Lights out is a classic logic puzzle played on a 5x5 grid of lights that are either on or off. Every time you tap a light, it flips, and the four lights directly above, below, left, and right of it flip with it: turning on what was off and off what was on. Your goal is to make every light go out. The puzzle looks like a memory game at first, but it is actually a pure logic problem, and every board has a pattern that solves it in the fewest possible taps. This version shuffles a new pattern every game, so no two puzzles are the same. There is no time limit, which makes the game a calm exercise in planning rather than a race. It rewards thinking a few taps ahead: a tap that helps the top of the grid may undo the bottom, so the order of your taps matters as much as the squares you choose. There is no account and no download, and your best move count is saved on your device.
How to Play
- Tap Start to shuffle a random set of lights.
- Tap a light to flip it together with its four neighbours: above, below, left, and right.
- Watch how each tap changes the surrounding lights before choosing the next one.
- Work the grid until every light is off.
- Finish in as few moves as you can; a new shuffle starts the next game.
- Your best move count is saved and shown with each result.
How the Score Is Calculated
Your score is the number of taps it takes to turn all the lights out, so fewer moves is a better result. There is no time limit, which means the score measures the quality of your logic, not your speed. A solve in fifteen taps is better than a solve in thirty, even if the second one came faster. Because every shuffle is different, no two boards require the same number of taps, so comparing your move counts across games is not always fair; the useful comparison is whether your solve was close to the board's minimum. Your best move count is saved in your browser, and the number to beat is your own best solve. The scoring rewards planning ahead, because a player who thinks two taps in front naturally uses fewer moves than one who reacts to each flip. Even a fifteen-tap solve on a fresh shuffle is a real result, and the trend across your games is the honest score to watch.
Tips to Improve
- Work the grid from the top row downward, making each row perfect before moving on to the next.
- Tap each light in the top row that is on, then let the flips cascade through the rows below.
- Once the top four rows are set, the bottom row often resolves by itself; tap it only if a light is still on.
- Before tapping, look at which lights will flip; a single tap can undo careful setup if you are not watching.
- Avoid tapping the same square twice in a row; the second tap just undoes the first.
- If the same pattern keeps returning, shuffle for a fresh board rather than burning moves on a stuck position.
- Keep a count of your taps as you go, so you know when a solve is getting long and can look for a shorter line.
- Solve a few boards from the top down to learn the standard shape, then experiment with shorter lines once the habit is automatic.
Common Mistakes
The most common mistake is tapping randomly to chase the last few lights. Random taps usually undo more than they fix, and a position that looks nearly done can take twice as many moves to clean up. The second mistake is ignoring the way a tap affects its neighbours; every tap changes five lights at once, and focusing on the one light you meant to change is how boards get worse. The third is re-tapping the same square. If the board looks the same after two taps, you have simply undone your own work. Finally, do not treat a high move count as a failure. A long solve still finishes the puzzle, and the second attempt on the same board shape is almost always shorter.