Backgammon

How to play

Your fifteen checkers travel towards your home board in the bottom right of the screen, and the game is won by bearing all of them off before your opponent does. Roll the dice, then tap a checker and tap where it should go. Doubles are played four times.

Landing on a point holding a single enemy checker sends it to the bar, and a player on the bar must bring that checker back before moving anything else. Once every one of your checkers is home you may begin bearing off.

The full rules, including the parts that are house choices, are in the Help drawer on the board itself.

Rules and controls

• The whole roll is the unit. You must use as many dice as you legally can, and when only one of the two can be played it must be the higher one. Moves that would break either rule are never offered.
• Gammons and backgammons. Two points if the loser has borne none off; three if they have borne none off and still have a checker on the bar or in the winner’s home board.
• The cube is owned. Anybody may double while it sits in the middle; after that only the player holding it. Declining costs the current value, not the doubled one.
• Crawford. The first game after either side reaches one point short of the match is played without the cube. It can be switched off.
• Keyboard and touch. Every point on the board is a real button with a name, so the game can be played with Tab and Enter as well as by tapping.

Modes

Quick game

A single game to one point. The fastest way in.

Match

Three, five, seven or eleven points, with the cube and Crawford.

Daily

Everyone gets the same dice today. Reloading will not change them.

Pass and play

Two players, one device, taking turns.

Practice

Take moves back and see the pip count. Nothing is recorded.

The opponent

The computer judges a position by pip count, the checkers it is leaving exposed and how easily each could be hit, the points it holds and whether they trap anything, its anchors, its home board and whether the game is still in contact or has become a pure race. Expert also weighs your reply across all twenty-one rolls before committing.

Casual

Misjudges positions the way a beginner does — it will leave a checker where it should not.

Steady

Sees the shape of the position but still misreads how much a blot costs.

Sharp

Rarely misjudges. Plays the best move it can see in one look.

Expert

Judges the position honestly, and weighs your reply across all twenty-one rolls first.

The levels differ mainly in how accurately they judge a position: the easier ones genuinely misread it rather than knowing the best move and playing a worse one. They never differ in the dice.

A few things worth knowing

• An anchor — two checkers on a point in your opponent’s home board — is what stops you being shut out. Breaking one for a small gain is how a comfortable game turns into a lost one.
• A blot six pips in front of an enemy checker is hit far more often than one eleven away, because six is the easiest number to make with two dice. Not all exposure costs the same.
• Once the two sides have passed each other nothing can be hit and the game is a pure race. Points and primes stop mattering entirely; only the pip count and how tidily you bear off do.

Privacy and local play

Your game, your settings and your record are stored on this device and nowhere else. There is no account, no sign-in and no gameplay request to any server. The reset button on the board clears this game’s saved data and leaves every other Zerdly tool alone.

Questions

Is this real backgammon?

Yes. Bar entry, blocked points, the mandatory dice-use rules, doubles played four times, bearing off with a higher die, gammons and backgammons, the doubling cube with ownership and the Crawford rule are all enforced by the rules engine — the same one the computer opponent plays from.

Does the computer cheat?

It cannot. The dice are rolled and placed on the board first, and the request sent to the opponent carries only the position and the roll already showing — there is no field in it for any other roll. Harder levels get a better judgement of the position, never better dice.

Can I reload to get a different roll in the Daily?

No, and not because it is forbidden. Each roll of the Daily is generated from the date and its position in the game, so roll fourteen is the same two numbers however you arrive at it. Reloading, taking a move back or coming back tomorrow all produce the same sequence.

Why will it not let me make a move?

Backgammon makes you use as many dice as you legally can, and if only one of the two can be played it has to be the higher one. A move that would waste a die you were obliged to use is not offered at all, rather than being accepted and then refused.

How good is the doubling cube play?

Deliberately simple. It doubles only with a clear lead in a pure race and takes unless the position is close to lost. Proper cube handling needs match equity tables and rollouts that this browser-only route does not have, so the checker play is the part to judge it on.

Is anything sent to a server?

No. The rules, the opponent, the dice, the sounds and your saved game all run in your browser. There is no account, and clearing this game's data leaves every other Zerdly tool untouched.

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