Reversi rules and how to play
Reversi is a two-player strategy board game played on a board of 8 by 8 squares with discs that are black on one side and white on the other. The game starts with four discs in the centre and Black moves first. A move places one disc so that it traps one or more of the opponent's discs in a straight line, and every trapped disc flips to the mover's colour. A player who cannot flip anything passes. When neither player can move, the player with more discs wins.
The same game is also sold under the trade name Othello®, a registered trademark of its owner; Ttakji is not affiliated with or endorsed by the trademark owner.
The board and the starting position
The board has 8 rows and 8 columns, 64 squares in total. Columns are named a to h from left to right and rows 1 to 8 from top to bottom. The game starts with four discs in the centre: White on d4 and e5, Black on d5 and e4. Black moves first and has four possible moves: d3, c4, f5 and e6.
How to play, step by step
- Black moves first. Players take turns placing one disc of their colour on an empty square.
- A move is legal only if the new disc and another disc of your colour trap one or more opposing discs in a straight line: across, up and down, or diagonally.
- Flip every trapped disc to your colour. If the new disc traps discs in several lines at once, all of those lines flip.
- Flipped discs do not flip further discs by themselves; only lines that end at the new disc count.
- If you have no legal move, you pass and your opponent plays again. On Ttakji this happens automatically.
- When neither player can move, usually when the board is full, count the discs. More discs wins; equal discs is a draw.
How discs flip
A line of opposing discs flips only when it is closed at both ends: by the disc you place and by another of your discs, with no empty square in between. A line that ends at an empty square or at the edge of the board does not flip. One move can flip discs in up to eight directions at once.
When a player cannot move
If you cannot place a disc that flips at least one opposing disc, you must pass and your opponent moves again. You cannot pass while you still have a legal move. On Ttakji the pass happens automatically and is shown to both players, so you never lose time on it. A player may have to pass several times in a row.
End of the game and the count
The game ends as soon as neither player can move. This usually happens when all 64 squares are filled, but it can happen earlier, for example when one colour has no discs left. Each player then counts the discs of their colour on the board. Empty squares are not counted.
- Neither player can move: the player with more discs wins.
- Neither player can move and both have the same number of discs: draw.
- Resignation or running out of time: the other player wins.
- A draw agreed by both players.
Strategy basics
A few simple ideas help more than counting discs early on.
Take the corners
A disc in a corner can never be flipped, and corners help you take whole edges. Be careful with the squares next to an empty corner (b2, g2, b7, g7 and the edge squares beside a corner): playing there often gives your opponent the corner.
Use the edges carefully
Edge discs are harder to flip than discs in the middle, but a lone disc on an edge can be attacked. Build edges that connect to a corner.
Keep your options open
Having many possible moves (mobility) matters more than having many discs in the middle of the game. Flipping fewer discs often leaves your opponent fewer good replies.
Think about the last move
Near the end, try to make the last move in each empty region of the board, so that your opponent has to move into it first.
Reversi vs gomoku
Reversi and gomoku are both two-player games with black and white pieces, but they are won in very different ways.
| Aspect | Reversi | Gomoku |
|---|---|---|
| Board | 8×8 squares, discs inside the squares | 15×15 lines, stones on the intersections |
| Pieces | Discs flip to the other colour when trapped | Stones never move or change colour |
| Goal | More discs when neither player can move | Exactly five in a row |
| First move | Black | Black |
| Length | At most 60 moves | Up to 225 moves |
| Passing | A player with no legal move passes | Never; there is always a free point until the board is full |
| Draw | Equal discs at the end | A full board without five in a row |
Playing on Ttakji
- Against the AI there is no clock, you can take back moves, and you choose Easy, Normal or Hard.
- Online and friend games give each player 30 seconds per move.
- If your 30 seconds run out, you lose. Your clock keeps running while you are disconnected.
- Black and White are assigned at random and swap on every rematch.
- You can resign or offer a draw at any time. Undo is only available against the AI.
- Ranked reversi games use their own Elo rating, starting at 1,200, and need Google sign-in.
Frequently asked questions
Is Reversi on Ttakji free? Do I need an account?
Yes. It is free and runs in your browser with nothing to install. Choose a nickname to play the AI, a random opponent or a friend by link. Sign in with Google only for ranked games and the leaderboard. When no other player is available, some random-match opponents may be AI.
What happens when I have no legal move?
You pass automatically and your opponent plays again; there is no pass button and no time is lost. If neither player can move, the game ends at once and the discs are counted.
How is the winner decided? Can a game end in a draw?
When neither player can move, which usually means the board is full, the player with more discs on the board wins. Empty squares are not counted. If both have the same number of discs, the game is a draw.
Who moves first, and does it matter?
Black always moves first. Against the AI you choose your colour; in online and friend games colours are assigned at random and swap on every rematch. With good play neither colour has a large advantage.
Is reversi the same game as the well-known brand-name version?
Yes, the basic rules are the same. Reversi is the generic name of the game; it is also sold under the trade name Othello®, a registered trademark of its owner, and Ttakji is not affiliated with or endorsed by the trademark owner. On Ttakji only the discs on the board are counted at the end.
How do I play Reversi with a friend?
Press "Play a friend" and send the link. It is a 1:1 game where each of you plays on your own phone or computer. The link works for 24 hours and neither of you needs to sign up.