Backgammon rules

What it is

Backgammon is a two-player race. Each side has fifteen checkers on a board of twenty-four points, and you are trying to move all of yours around to your own corner and then off the board before your opponent does. The dice say how far you may move; you choose what to move. What stops it being pure luck is that a lone checker can be knocked back to the beginning, so every move is a bet about what your opponent might roll next. It is about five thousand years old. This page describes the game as it is played at jpgames.app, including the Turkish variants in the table settings.

The board

Twenty-four narrow triangles, called points, in four quadrants of six. Each player has fifteen checkers and moves in the opposite direction to the other — your 1-point is your opponent's 24-point.

The last six points, where you are heading, are your home board. Once all fifteen of your checkers are home, you can start taking them off.

The ridge down the middle is the bar, where knocked-off checkers wait.

The deal — the opening roll

Each player rolls one die. Higher number goes first, and plays both dice as their opening move. A tie is re-rolled.

Play

Roll two dice. Each die is a separate move of that many points, in your direction of travel — you may move one checker twice or two checkers once each.

Doubles are played four times. Roll 3-3 and you make four moves of three.

A point is open to you unless your opponent has two or more checkers on it. Two of theirs makes it a block you cannot land on.

You must use both dice if there is any legal way to do so. If only one can be played, you must play the higher one. If neither can, you forfeit the turn.

Hitting. Land on a point holding exactly one opposing checker and it is hit — it goes to the bar and must re-enter the board from the very beginning of its journey. A player with a checker on the bar must bring it in before making any other move, and if they cannot, they lose the whole turn.

Bearing off. Once all fifteen of your checkers are in your home board, a roll may take a checker off the board entirely. If you roll higher than any occupied point, you may bear off from the highest one you have. First player to bear off all fifteen wins the game.

The doubling cube

A six-sided block showing 2, 4, 8, 16, 32 and 64. It is what turns backgammon from a board game into a gambling game, and it is only in play in the Western variant.

At the start of your turn, before you roll, you may double — offering to play for twice the current stake. Your opponent either refuses, and loses the current stake immediately, or accepts, and now owns the cube: only they may make the next double.

Knowing when to double, and when to drop, is most of the skill in match play.

Scoring

A single game is worth one point, unless it ends badly for the loser:

All of that is then multiplied by the doubling cube.

In the Turkish variants, where there is no cube, a backgammon collapses to the gammon value — the worst you can lose is double.

Ending the game

Backgammon is played as a match to a number of points, not as a single game. Games are played one after another and their values accumulate until somebody reaches the target.

The default match length is 7 points with the cube on, and 5 without it. The table settings offer other lengths.

Variants we implement

1. Western Standard — the default. Hitting sends checkers to the bar, the doubling cube is in play, and a backgammon is worth triple.
2. Tavla — the Turkish standard game. Same board, same movement, same hitting, but no doubling cube, and a backgammon counts as a gammon rather than triple.
3. Plakoto — the board is the same, but a checker landing on a lone opposing checker pins it instead of hitting it. The pinned checker stays exactly where it is and cannot move until the pinning checker leaves. Trapping a checker on your opponent's own 1-point can decide the game outright. No cube.
4. Gul Bara — also called Moultezim. All fifteen checkers start stacked on a single point, and there is no hitting at all: a lone opposing checker simply blocks the point. It is a pure race with blocking, and it plays quite unlike the others. No cube.
5. Match length and the doubling cube are set at the table.

Where we differ from the common rules

1. Two players only. A bot fills the other seat. Chouette — the multiplayer cube game — is not implemented.
2. No Crawford rule, and no post-Crawford doubling conventions. Match play here does not restrict doubling when one side is one point from victory.
3. No beavers, raccoons or the Jacoby rule.
4. No automatic doubles on a tied opening roll — a tie is simply re-rolled.
5. Plakoto and Gul Bara are simplified. Plakoto does not implement the mother checker rule that some tables use, and Gul Bara does not implement the variant entry restrictions of full Moultezim.

Ready to play? Start a Backgammon table — a bot fills the other seat, so a game starts whenever you do.

For the wider game, including the match conventions above that we do not implement, see Backgammon on Wikipedia.

Common questions

How do you win at backgammon?

By moving all fifteen of your checkers around the board into your home board and then bearing them all off before your opponent does.

What happens when you get hit in backgammon?

Your checker goes to the bar and must re-enter from the far end of the board, losing all the ground it had made. You cannot make any other move until it is back in play.

What is the doubling cube for?

It offers to double the stake of the current game. Your opponent either accepts — taking ownership of the cube, so only they can double next — or refuses and concedes the game at its current value. It is only in play in the Western variant.

What is a gammon in backgammon?

Winning while your opponent has not borne off a single checker. It is worth double. A backgammon, worth triple, is the same thing but with one of their checkers still on the bar or in your home board.

What is the difference between Plakoto and standard backgammon?

In Plakoto, landing on a lone opposing checker pins it in place instead of sending it to the bar. It cannot move at all until you move off, so trapping a checker early can decide the game.