Rules of Go

For the UK Go Challenge, we have provided Andreas Fecke's cartoon booklet Go - An Introduction both in printed form and on the BGA web site. This booklet is suitable for both children and adults, and for many people it will be the only thing they need to read in order to play in the UK Go Challenge. Even if you are a Go player already, it is worth reading it so that you know how Go has been explained to your children.

This page provides a more formal and concise statement of the rules. It will help you if you need to clarify some question or to resolve a misunderstading or disagreement. If you are new to Go, we recommend that you read Go - An Introduction and perhaps try a couple of games on a 9x9 board before you read this page.

In addition to the rules, we have provided Guidelines for Common Situations that identify some common misunderstandings that beginners sometimes have, recommends ways of overcoming them, and guides you on how to deal with any questions that may arise during games.

"He", etc, below refers to "he" or "she" as appropriate.

1. Equipment

Games in the UK Go Challenge are played using a board marked with a grid of 13 horizontal and 13 vertical lines, and a supply of black and white "stones". Approximately 80 stones of each colour are enough - the exact number is not important.

The intersections of the grid are called board points, or just points. Stones are placed on the intersections, not in the squares. The intersections at the sides and corners of the grid are used as well as those in the middle, so a 13x13 board has 169 board points altogether.

2. Conduct of the Game

2.1 The game starts with the board empty. One player has the black stones and the other the white stones. (In the UK Go Challenge, the colours are assigned by the tournament organiser doing the pairings). The players play alternately, with Black making the first play.
2.2 Board play: A play consists of placing a stone of the player's own colour on an unoccupied board point and then removing any stones that are now captured according to the capturing rule (section 3). When a player captures any of his opponent's stones, he keeps them as prisoners.
2.3 Pass play: If the player whose turn it is does not wish to place a new stone on the board, he may instead give up his turn by saying "Pass" and giving a stone as an extra prisoner to his opponent.
2.4 Game end: When both players pass consecutively, the game ends and the players determine the result (section 5). However, to make sure the number of moves is the same for both players, white must pass last, even if this means a third pass in a row.
2.5 Resignation: Either player may concede defeat at any time by saying "I resign", and his opponent then wins the game.
2.6 Offering a draw: Players are not permitted to offer or accept draws. The only way for a game of Go to be a draw is as a result of a tied score.
2.7 Running out of stones: If a player runs out of stones before the end of the game, the players should return equal numbers of prisoners to their opponent. In the rare cases when this isn't possible, a second set of stones should be brought into service to complete this game. A player must never be deemed to lose a game because he has run out of stones.

3. Capturing stones

Any set of stones of the same colour, all which are connected together along the grid lines (not diagonally), forms a single unit. A single stone not connected to any other stone of the same colour forms a unit by itself.
For example, here we have two units, one of a single stone (marked) and one of three stones (unmarked). They are separate units because the marked stone is not adjacent to any of the others along a grid line.

Unoccupied points adjacent to a unit along a grid line (not diagonally) are called the liberties of that unit.
Thus the 3-stone unit in the previous example has 7 liberties, marked with an x here.

If a player places a stone on the last liberty of an enemy unit, so that it now has no liberties, then he removes all the stones of that unit from the board and keeps them as prisoners.
Here, six of the 3-stone unit's seven liberties are occupied by white stones, and it has only one liberty left. If it's White's turn ...

... he can play here, taking the last liberty of the 3-stone unit. After playing this stone, White immediately removes the three black stones.

The position on the board will now be like this. White keeps the three prisones to one side until the end of the game.

Note that the remaining black stone is not captured, as it still has two liberties (marked).

4. Prohibited plays

4.1 Repetition: A board play must not recreate a board position that has previously occurred after any of that player's turns earlier in the game.
4.2 Suicide: A board play that leaves a unit of the player's own colour with no liberties after the removal of any captured stones of the opponent's colour is not permitted.
For example, White is not allowed to play the marked stone, because it would have no liberties.

But when the black stones have no other liberties, White can play there, because it takes the last liberty of the black stones and thus captures them. When the black stones are removed, the marked white stone ends up with liberties where they were.

5.Determining the Result

Once both players have passed in succession, the game is finished and they determine the result using the following steps:

5.1 Remove dead stones

Any stones which both players agree would inevitably be captured if play continued are now removed from the board and kept as prisoners. (If the players find that they don't agree whether some stones could be captured or not, they should follow the procedure for settling questions of life and death (section 6) before removing any stones.)

5.5 Recognise territories

After dead stones have been removed, the board will be broken up into regions consisting of vacant points surrounded by live stones and the edges of the board. When all the stones bordering such a region are of the same colour, then the vacant points in that region are territory for that colour. A region whose boundary contains stones of both colours is not territory for either player.

Here, for example, the lower right corner of the board contains 12 points of Black territory, but the 12 board points in the lower left corner are not territory for either player.

5.3 Work out the result

Each player now scores a point for each vacant board point inside his territories, and a point for each prisoner he has captured. The white player scores and extra 7 points called "komi", to make up for the disadvantage of going second. The player with more points is the winner.

6. Settling questions of life and death

After the game is over, the life or death of stones depends on the players' agreement. It is not adjudicated, and must not be discussed by bystanders in the players' presence. If the players have different opinions about the status of some stones, they should resolve it by playing on until the position is clear to them both, using the normal rules plus the additional special rules listed below.

Back to UK Go Challenge Last update: 28th November 2007