Reversi — Free Online Board Game
Flip the balance on an 8×8 board
Runs in your browser · nothing is uploaded
Change the board. One disc.
The balance can shift until the very last move
Changing mode starts a new game.
Legal moves: 4
Last move: —
The playbook
Black starts. Sandwich an unbroken line of opposing discs between your own to flip them. Lines can run horizontally, vertically or diagonally. Dots show every legal move.
When neither side can move, the side with more discs wins. A player with no legal move passes automatically. The casual computer weighs corners and future move options.
Tab to the board, use arrow keys to navigate, then Enter or Space to play.
Against the computer, Undo takes back your move and all computer responses together.Every disc can change sides
Reversi starts with four discs in the center of an 8×8 board. Place a disc to trap the other color and flip the captured line. The current score is useful, but the final disc count decides the winner.
How to play
- Select Play computer or Two players. Black starts, and you control black against the computer.
- Look for the small dots: these mark legal moves for the current player.
- Place a disc to bracket one or more opposing discs. Every captured horizontal, vertical and diagonal line flips.
- Watch the live black and white counts. Use Undo to revisit the last decision or New game to reset.
The last placed disc has an orange mark. A player without any legal move passes automatically, and the page announces the pass. In computer mode, Undo takes back your move and all computer responses to it.
Rules and a first-move example
From the standard opening position, black can play row 3, column 4. The white disc at row 4, column 4 is bracketed by the new black disc and the existing black disc at row 5, column 4. It flips, giving black four discs and white one.
A move must flip at least one disc. You cannot voluntarily pass when a legal move exists. The game finishes when neither side can move, including when the board is full. More discs wins; equal counts draw.
Try protecting the corners
A corner disc cannot be flipped, which makes corners valuable. The casual computer considers corners, risky nearby squares, available replies and disc count. It is a practice opponent, not an unbeatable engine.
Keyboard users can Tab to the board, navigate with arrow keys, and play with Enter or Space. The game runs in your browser; moves are not uploaded. Progress stays in memory and resets when the page is refreshed or closed.
FAQ
What makes a move legal?
Your new disc must trap at least one uninterrupted line of opposing discs between itself and another disc of your color. All trapped lines are flipped.
What happens if a player cannot move?
Their turn passes automatically. If neither player has a legal move, the game ends even if some squares are empty.
How is the winner decided?
The side with more discs when the game ends wins. Equal disc counts produce a draw.
Can I undo the computer's move too?
Yes. Undo returns to the position before your last decision, including every computer response if your turn was passed. Refreshing clears the game and its history.
