Reversi
The classic board game of flips and corners. Place a disc to trap a line of your opponent's discs between two of yours and they all turn to your colour. Play black or white against an AI on Easy, Normal or Hard, with legal-move dots, hints, undo and a win record for each level. Grab the corners, keep your options open and finish with the most discs.
How to play Reversi
⌨️ Keyboard & mouse
Click a square to place a disc
- Free, no sign-up
- Plays in the browser
How Reversi works
The board starts with four discs in the middle, two of each colour. On your turn you place one disc so that a straight line of the opponent's discs — across, down or diagonally — is trapped between the disc you just placed and another one of yours. Every trapped disc in that line flips to your colour, and a single move can flip in several directions at once.
You may only play where at least one disc flips. When no such square exists your turn is skipped, and the game ends when neither player can move, which is usually once the board is full. Whoever has more discs on the board wins, no matter who was ahead along the way.
That last part is why the game turns on the corners. A disc in a corner can never be trapped between two others, so it can never be flipped, and it anchors the edges next to it. The squares diagonally next to an empty corner are the dangerous ones: playing there hands the corner over. Our board marks every legal move with a dot, and the hint button points out a move worth considering rather than simply the one that flips the most.
Tips for Reversi
- Corners can never be flipped back. Aim for them, and avoid the squares right next to an empty corner.
- Early on, having more moves beats having more discs. Keep the AI short of good options.
- Edges are strong once you can hold them. Don't give your opponent a way onto the edge behind you.
- Hard mode reads the last ten moves perfectly, so the end game needs care.
