Different Sized Boards

Table of contents Different sizes Unusual properties Miscellaneous Elsewhere Edgeless board Increasing board

Table of diagrams Edgeless game. ladders don't work. 1x2 board. What happens if this becomes 1x3 board when white plays once... Black's bad result. But even if white plays more, this board increases unto the next right intersection(In Chinese rules, white can get more points forever). Black's best result. Even if white plays on the left point, the board increases but it's suicide. 2x2 board. Black wins. 2x1 board. Black wins.

The game of go is usually played on a board with two orthogonal sets of 19 lines. Such a board is said to have a size of 19x19. It is certainly possible to play Go on a board of any desired size, so long as one can find a way to represent the board and has enough stones to fill it. Most computer go programs allow one to choose the board size. Some programs allow boards which are rectangular, such as a 13x19 board, while others require the board to be square. One can also take a typical 19x19 goban from the real world and shrink it to a smaller size using various techniques to mask out the nonessential lines.

This section is dedicated to exploring the implications on play of different sized boards that have existed historically, traditionally and experimentally, as well as any related culture.

Different sizes

(up to) 2x2: Results of games up to 2x2 http://web.archive.org/web/20080509132201/http://www.brooklyngoclub.org/jc/go2by2.html

5x5

Commonly used to introduce the game using capture go.

6x6

smallest square board where white can create a 'normal' living group if black plays optimal.

7x7

The smallest undecided board with an odd number of lines (Proofs?! --RobertJasiek).

9x9

Popular for fast and instructive games.

11x11

Uncommon board size.

13x13

Also popular.

15x15

Popular in China many years ago. 15x15 was also promoted briefly by the Nihon Kiin for the purpose of promoting the game amongst junior players. 15x15 is also the official board size for Renju (competitive version of Gomoku).

17x17

Currently used in Tibetan go. In ancient China it was the mainstream size before Jin Dynasty (265 AD - 420 AD), and was thoroughly replaced by the 19x19 board during Tang Dynasty (618 AD - 907AD) source.

19x19

The default size in the current era. The earliest 19x19 board appeared during Han Dynasty (206 BCE - 220 AD), and became mainstream size during Southern & Northern Dynasties (420 AD - 589 AD) source. Why19x19

Aside from actual play, smaller boards are often used in books for presenting problems or instruction purposes. Examples:

• Book of 105 problems on 4x4 board (Japanese), by Cho U (ISBN-13: 978-4344979765, Kindle editon ASIN: B07CKY1VK5)
• How to Improve on a 5x5 Board by Fukui Masaaki, which was recently translated to English
• An introductory book by Nihon Kiin using 7x7 board (Japanese, ISBN-13: ‎978-4344977853)
• As ealy as 1918, an introductory book by Suzuki Tamejiro used 11x11 board diagrams including a hypothetical full game record. He called it as his "own innovation".

See also Interesting board sizes and Small Board Go.

Unusual properties

Even-sized boards

Why not?

Small boards

17x17 and smaller.

Large boards

21x21 and beyond.

Rectangular boards

19x13 and others.

Narrow Boards

2xN and others.

Linear boards

1xN

Miscellaneous

Unusual gobans

Boards with holes, strange shapes and other weirdness.

How to shrink a goban

Techniques to turn a standard board into a smaller one.

The biggest goban

NetGo

Possible rule set for non-standard boards

Elsewhere

• At goproblems.com, Andreas Fecke, by the username of ferdi has created a series of 4x4 problems. The problems are generally difficult, precision is needed to solve them.

Edgeless board

This part contains about a board that has no edge. If a board has no edge, both player's playing would increase forever. So even if both players construct their territories, stopping the game at random timing is illegal. But if they play forever, the game can't be finished. And if the ruleset is that "territories creating faster wins", White tries to block black's territories creating. So the ruleset is able to be only in "Handicap games" or "games that start from both stone's arrangement". But people would disbelieve "What is the point of playing on a edgeless board with changed rules".

Edgeless game. ladders don't work.  

[edit]

Increasing board

This part contains about boards that increase unto the next right intersections when white plays once.

1x2 board. What happens if this becomes 1x3 board when white plays once...  

Black's bad result. But even if white plays more, this board increases unto the next right intersection(In Chinese rules, white can get more points forever).  

Black's best result. Even if white plays on the left point, the board increases but it's suicide.  

2x2 board.  

Black wins.  

2x1 board.  

Black wins.