Backgammon Rules

What You Need

Players

Backgammon is a game for two players. Each player competes to be the first to move all their checkers off the board.

The Board

A backgammon board has 24 narrow triangles called points, arranged in alternating colors. The board is divided into four quadrants of six points each. Each player has a home board (inner board) and an outer board, separated by a raised divider called the bar.

Checkers

Each player has 15 checkers (also called men, pieces, stones, or counters) of their own color. These are moved around the board according to dice rolls.

Dice

Two standard six-sided dice are used. In physical play, two pairs are used (one per player) and precision dice (evenly weighted and balanced) are preferred in tournaments. Online, a single pair of server-generated random dice ensures fair play.

Dice Cups

Each player uses a cup to shake and roll the dice onto the board. This prevents dice manipulation. Some players use a baffle box instead, where dice are dropped through a sloped chute.

In online backgammon, dice are rolled automatically by the server to ensure fairness.

The Doubling Cube

The doubling cube is an oversized die with the numbers 2, 4, 8, 16, 32, and 64 on its faces. It tracks the current stakes of the game and adds a critical layer of strategy.

Setting Up the Board

Each player places their 15 checkers in the following starting position:

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

Your checkers move from your opponent's home board, through their outer board and your outer board, into your own home board. Your opponent moves in the opposite direction.

Object of the Game

Move all 15 of your checkers into your home board, then bear them off (remove them from the board). The first player to bear off all their checkers wins the game.

Starting the Game

Each player rolls a single die. The player who rolls the higher number goes first, using both their own number and their opponent's number as their opening move. In other words, the opening player uses both numbers(their own die and their opponent's die) for their first turn. If both players roll the same number, they re-roll until the numbers differ. After the first move, players alternate turns, rolling their own pair of dice.

Movement Rules

Checkers always move forward (toward your home board) according to the numbers shown on the dice.

1. Two separate moves. The numbers on the two dice are treated as separate moves. You may move one checker the total of both dice, or move two different checkers - one for each die. For example, a roll of 6-3 means you can move one checker 9 spaces, or move one checker 6 and another 3.
2. Open points only. You may move a checker to any point that is: occupied by your own checkers, empty, or occupied by exactly one opponent checker (a blot). You cannot move to a point with two or more opposing checkers.
3. Doubles. When you roll doubles (e.g., double 4s), you play the number four times instead of two. You can distribute these four moves among your checkers in any legal combination.
4. Use the full roll. You must use both numbers if possible. If only one can be played, you must play the higher number. If neither can be played, the turn is forfeited.

Points and Primes

When two or more of your checkers occupy the same point, it is called a made point or owned point. Your opponent cannot land on it, but may jump over it. There is no limit to how many checkers can stack on a single point.

Several consecutive made points form a prime. If you create a full prime - six points in a row - any opponent checkers behind it are completely trapped until the prime breaks.

Hitting and Blots

A single checker sitting alone on a point is called a blot. If your opponent lands on your blot, it is hit - your checker is removed from the point and placed on the bar.

The Bar and Re-entry

The bar is the raised divider running down the center of the board. A checker on the bar is out of play until it re-enters the game.

To re-enter, you must roll a number that corresponds to an open point in your opponent's home board (points 1-6 from their perspective). If both numbers are blocked, your turn is lost. If your opponent owns all six points in their home board (a closed board), you cannot enter at all - you must wait until they open a point.

If you can enter with one die but not the other, you must enter with the available die and forfeit the remaining number.

Important: You must re-enter all checkers from the bar before you can move any other checker. Once re-entered, any remaining numbers on the dice may be used normally.

Bearing Off

Once all 15 of your checkers are in your home board, you may begin bearing off. Roll the dice and remove checkers from the corresponding points:

• A roll of 3-2 lets you take one checker off the 3-point and one off the 2-point (if you have checkers there).
• Instead of bearing off, you may move checkers within your home board.
• If you roll a number higher than your highest occupied point, you must bear off a checker from the highest point that has checkers.
• If a checker is hit during bearing off, it must re-enter and travel all the way back to your home board before you can resume bearing off.

The first player to bear off all 15 checkers wins.

The Doubling Cube

Introduced in the 1920s, the doubling cube transformed backgammon from a simple race into a game of deep strategy and calculated risk.

Before the game starts, the cube sits in the center showing 64 (which represents a value of 1). Either player may double the stakes before their roll on any turn. The opponent then chooses:

• Accept (take):Play continues at double the stakes. The player who accepted now "owns" the cube and is the only one who may re-double later.
• Decline (drop/pass): The declining player concedes the game at the current stakes.

There is no limit to re-doubles, but in practice the cube rarely exceeds 4 or 8.

In match play (playing to a set number of points), the doubling cube adds strategic depth:

The Crawford Rule

The Crawford Rule applies: when one player is exactly one point away from winning the match, the doubling cube cannot be used for one entire game. This rewards the leader and prevents the trailing player from automatically doubling every game with nothing to lose. After the Crawford game, the cube is available again.

Scoring

Single Game

If the losing player has borne off at least one checker, it is a single game. The winner scores the current value of the doubling cube (or 1 if the cube was not used).

Gammon (Double Game)

If the loser has not borne off any checkers, it is a gammon. The winner scores twice the cube value.

Backgammon (Triple Game)

If the loser has not borne off any checkers andstill has a checker on the bar or in the winner's home board, it is a backgammon. The winner scores three times the cube value.

Optional Rules

These rules are commonly used in casual and money play, but not in standard tournament play:

1. Automatic Doubles: If both players roll the same number when determining who goes first, the cube automatically turns to 2. Usually limited to one automatic double per game.
2. The Jacoby Rule: Gammons and backgammons only count as a single game unless the cube has been doubled. This encourages faster doubling and quicker games.
3. Beavers: When doubled, a player may immediately re-double (beaver) while keeping possession of the cube. This is used when the player being doubled believes they are actually the favorite.

Etiquette and Procedure

The following conventions apply to physical backgammon. In online play, the game enforces these rules automatically.

1. Roll dice on your right-hand side of the board.
2. Both dice must be rolled together and land flat. Re-roll if a die lands outside the board or is tilted (cocked).
3. Your turn is not over until you pick up your dice. Your opponent cannot roll until you have completed your move and picked up.
4. If you roll before your opponent picks up their dice, they may require you to re-roll.
5. An illegal move may be corrected as long as the next player has not yet rolled. After that, the move stands as played.