Backgammon scoring and matches

Single, gammon and backgammon

The winner of a game is the first player to bear off all fifteen checkers. How many points they score depends on how far the loser got.

A single game is worth 1 point: the loser had borne off at least one checker. A gammon is worth 2: the loser hadn't borne off any. A backgammon is worth 3: the loser hadn't borne off any and still had a checker on the bar or in the winner's home board.

The cube multiplies the score

Those points are then multiplied by the value on the doubling cube. Win a single game with the cube on 2 and you score 2 points. Win a gammon with the cube on 4 and you score 8.

A player who passes a double loses at once, scoring the other player the cube value from before the double, as a single game. A player who resigns gives up a single, a gammon or a backgammon of their choice, times the cube.

Playing a match

Most serious backgammon is played as matches: the first player to reach a set number of points wins. Matches are usually an odd length, such as 3, 5, 7 or more. Points from the last game can overshoot: if you need 2 points and win a gammon with the cube on 2, you still win the match.

On OneGammon you can play a single game, which is a 1-point match, or a match to 3, 5 or 7 points, with or without the cube. The score is shown beside each player's name.

The Crawford rule

The first time a player gets within one point of winning the match, the next game is the Crawford game, and it is played without the cube. Without this rule the trailing player would always double straight away, since they have nothing to lose. After the Crawford game, doubling is allowed again.

For example, in a 5-point match leading 4-2, the next game is played without the cube. If your opponent wins it and the score becomes 4-3, the cube is back for the game after.

Why the score changes how you play

The score changes what each point is worth. When a single game decides the match, gammons count for nothing extra, so you play only to win the game. When you are behind, a gammon can be worth far more than in a normal game, so it is worth taking risks for one.

OneGammon's computer chooses its moves and its cube decisions by the match score, the way strong players do.

Games played for points

Outside matches, backgammon can be scored game by game, each one settled on its own. This is called a money game, because the points are traditionally played for a stake. OneGammon is free and has no money play of any kind: every game is a match to a set number of points.