19x19

19x19 refers to a grid formed by 19 vertical and 19 horizontal lines, creating 361 intersections. This grid is the standard board size for the board game Go (known as goban in Japanese). While 19x19 is the common size for official and competitive play, smaller boards such as 9x9 and 13x13 are used for teaching, shorter games, or quicker play.

Go is a two-player strategy game in which players alternately place stones on the intersections of the grid. Black typically plays first. The objective is to control more territory on the board by surrounding empty points with stones. Stones are captured when they are completely surrounded by the opponent’s stones. Play continues until both players pass. On a 19x19 board, games can be lengthy and highly strategic, with openings and middle-game plans evolving over many moves. The board features nine star points to aid orientation, located at the intersections (4,4), (4,10), (4,16), (10,4), (10,10), (10,16), (16,4), (16,10), and (16,16). Coordinates are commonly given as a letter for the column and a number for the row, with columns labeled A–T (skipping I) and rows numbered 1–19.

Historically, Go originated in China more than two millennia ago and later spread to Korea and Japan, where the 19x19 board became the standard for serious play. In the modern era, the 19x19 board is used in professional competitions and AI research, as well as in digital versions and teaching tools, while smaller boards remain popular for learning and casual play.