Lights Out

Lights Out is a 5x5 grid logic puzzle with a satisfying twist. Each of the 25 tiles is either lit or dark, and pressing any tile flips it together with its four orthogonal neighbours up, down, left, and right. Corner and edge tiles reach fewer neighbours, so every move sets off a small chain reaction across the board. The goal is simple to state but tricky to reach: switch off every light at once.

Every board on this page is generated by pressing random tiles on a fully dark, solved grid. Because a single press is its own inverse, the exact sequence that built a puzzle also solves it, which means each layout is mathematically guaranteed to be solvable with zero guesswork. No two puzzles are alike, and a brand new arrangement is always one tap away.

You can play with a mouse, a touchscreen, or the keyboard. Click or tap any tile, or steer a cursor with the arrow keys and press space to flip. A live Moves and Lit counter keeps track of your progress, and the New button reshuffles instantly. Difficulty stays fair because every scramble follows the same rules, so you are never handed an impossible board.

The entire game is a single HTML file with nothing to download and no account to create. It runs fully offline inside your browser, scales cleanly from phone to desktop, and respects your privacy by tracking nothing. There are no ads inside the play area, so you can focus purely on the puzzle in front of you.