Backgammon Rules

Backgammon is a two-player board game combining strategy and luck, played with checkers and dice on a board of 24 triangles (“points”). This page describes the standard rules of the game.

Note

JustGammon currently implements standard single-game backgammon (no doubling cube and no match play). The rules below describe the full traditional game; the How to Play guide describes what’s available in the app today.

Objective

The goal is to move all 15 of your checkers around the board into your home board and then bear them off (remove them from the board) before your opponent does the same.

The board

• The board has 24 triangular points, grouped into four quadrants of six points each: your home board, your outer board, your opponent’s outer board, and your opponent’s home board.
• Each player has 15 checkers of one color.
• Checkers move in opposite directions for each player, both ultimately traveling toward — and then off — their own home board.

Starting position

Each player starts with checkers arranged as follows (using the standard numbering where point 1 is a player’s own furthest point in their home board and point 24 is the opponent’s furthest point):

• 2 checkers on the 24-point
• 5 checkers on the 13-point
• 3 checkers on the 8-point
• 5 checkers on the 6-point

The opponent’s setup mirrors this from their own perspective.

Movement

• Players alternate turns. Each turn starts by rolling two six-sided dice.
• A checker may be moved to any point occupied by zero, one, or more of your own checkers, or by exactly one opposing checker.
• The two dice values are played as two separate moves, either on the same checker (moving it the sum of both dice, provided each intermediate point is legal) or split between two different checkers.
• Doubles: if both dice show the same number, that number is played four times instead of two.
• If a player cannot use one or both dice, that part of the turn is forfeited. If a die (or the full roll) cannot legally be played at all, it is skipped.
• Players are required to use as many of the dice values as legally possible, using both if the position allows it.

Hitting and the bar

• A point occupied by exactly one opposing checker (a “blot”) can be hit: the opposing checker is placed on the bar.
• A player with one or more checkers on the bar must re-enter them into the opponent’s home board before making any other move. A checker re-enters on the point corresponding to a rolled die, provided that point isn’t blocked by two or more opposing checkers.
• If a player cannot re-enter a checker from the bar because all the relevant entry points are blocked, they forfeit the rest of that turn.

Bearing off

• Once a player has moved all 15 of their checkers into their home board, they may start bearing off — removing checkers from the board.
• A die value bears off a checker from the matching point (e.g. rolling a 6 bears off a checker from the 6-point).
• If there is no checker on the exact point matching a die value, the player must first make a legal move within the home board if possible; otherwise, if there are no checkers on any higher-numbered point, a checker may be borne off from the highest point below the die value.
• If any checker is hit and sent to the bar during bear-off, that player must bring it all the way around the board again before resuming bear-off.

Winning

• The first player to bear off all 15 checkers wins.
• If the losing player has already borne off at least one checker, it’s a single win (also called a “single game”).
• If the losing player has borne off no checkers, it’s a gammon — traditionally worth double.
• If the losing player has borne off no checkers and still has a checker on the bar or in the winner’s home board, it’s a backgammon — traditionally worth triple.

The doubling cube

In tournament and money-game backgammon, a doubling cube is used to raise the stakes of a game. Either player, on their turn before rolling, may propose doubling the value of the game; the opponent must either accept (taking control of the cube for future doubles) or decline (conceding the game at its current value). This is a standard part of the traditional game, but is not currently part of JustGammon.

Match play

Backgammon can also be played as a single game (as in JustGammon today) or as part of a match to a target score across multiple games, with the doubling cube and gammon/backgammon multipliers contributing to the running score. JustGammon currently plays single games rather than matches.