What is Gomoku on 13×13 and 19×19 boards?
Gomoku is usually played on a 15×15 board, but the rules work on any size. Here you can also choose a 13×13 board or a 19×19 board in the table setup. Black still moves first, a line of exactly five stones still wins, and every opening and rule set can be combined with any of the three sizes.
On 13×13 the edges are closer to the centre, so games are shorter and lines run into the edge sooner, which makes defending a little easier near the sides. On 19×19, the board of Go, there is far more room: attacks can start far apart and a draw by a full board is almost impossible.
Omok, Connect6 and Gomoku with captures start on 19×19 by default, because that is the board they are traditionally played on.
Rule changes
| Rule | Standard Gomoku | Gomoku on 13×13 and 19×19 boards |
|---|---|---|
| Board | Standard Gomoku15×15 points. | Gomoku on 13×13 and 19×19 boards13×13 points for a quick game, or 19×19 points, the size of a Go board. |
| How to win | Standard GomokuMake an unbroken line of exactly five stones. | Gomoku on 13×13 and 19×19 boardsThe same on every board size. |
| Draws | Standard GomokuThe board fills up with no winning line, which almost never happens. | Gomoku on 13×13 and 19×19 boardsThe same rule; a full board is a little more likely on 13×13 and practically never happens on 19×19. |
History
Five in a row began on the Go board, and in Japan the game was long played on 19×19 points. Japanese players later settled on the smaller 15×15 board, which became the standard for both Gomoku and Renju and is the size used in tournaments today.
The Go board never went away. Omok in Korea, Connect6 and the capture games descended from Ninuki-Renju are all played on 19×19, and many casual players still use whatever Go board they have at hand. Smaller boards such as 13×13 are a common choice for quick games and for learning, since the shorter edges keep the game compact.