Reversi Analysis

Squares are named as in chess, by column, a to h from the left, and row, 1 to 8 from the bottom: a1 is the bottom-left corner. Black's moves are dark and white's light. A line's percentage is the player to move's score after its first move: the share of the points they can expect, a win counting 1 and a draw ½, which is what the computer ranks moves by. The bar under it shows their chances of a win, a draw and a loss. Near the end, from about 16 empty squares, the computer works out perfect play: then each line plays perfectly, and its score is the final margin, so +6 means the player to move wins by 6 discs. A pass in the moves marks a player with no legal move. The computer's best move is ringed in gold on the board. Click a move in a line to play the line out to there; point at a line to see its first move on the board.