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An empty go board, with the 19x19 intersecting lines

The Go board, called the goban ?? in japanese, is the playing surface on which to place the stones. The standard board is marked with a 19x19 lined grid. Other smaller boards include a 13x13 grid and a 9x9 grid used for shorter games often used to teach beginners. Some 19x19 boards have a 13x13 grid on the reverse side. 17x17 was used in historical times. Chinese boards are generally square; Japanese and Korean boards are slightly longer than wide, so that they appear square when viewed from a normal playing position. In Asian go parlors, the tables are slightly lower than the typical game table so that the players can see the position more clearly.

Traditional Japanese goban usually follow the dimensions:

                           		mm          inch
Board width              		424.2     16 23/32   1.4  shaku ?
Board length              		454.5     17 29/32   1.5  shaku ?
Board thickness           	151.5      5  31/32   0.5  shaku ?
Line spacing width-wise    	  22             7/8      7.26 bu ?
Line spacing length-wise   	  23.7        15/16     7.82 bu ?
Line thickness              	    1            1/32     0.3  bu ?
Star point marker diameter  	    4            5/32     1.2  bu ?
Stone diameter             	  22.5        29/32     7.5  bu ?

(1 inch = 25.4?mm; 1 shaku = 100 bu = 303?mm)

Go boards fall into several types or styles.

• Economical boards are made of paper, plastic or laminate, which can easily be folded away and stored. They are often used by beginners or for when one does not have a proper set available. A board can be hand-drawn on a stiff piece of cardboard for the super-economical.
• Magnetic sets are also available, with magnets in the stones and a metallic board. They are useful for travelling. Large magnetic boards are also available for demonstration purposes, during lectures and other presentations.
• Wooden board one to two inches thick are commonly used. They are known as "table boards" because they are placed on a table (in contrast see "floor board" below.) The wood grain is pleasing to the eye, and the stones make a nice sound when placed firmly on the board. They can be made to be folded, or slotted together. Some have grids on the reverse. Although boards have been made from almost every type of wood including cheaper kinds made of pressed particle board with or without veneer; a light color with a fine grain that does not compete with the grid lines is considered most suitable, such as spurce or katsura ?. The most valued boards are made from kaya, which is a mellow yellow in colour. Bamboo boards are also available; they appeal especially to those interested in fast-growing sustainable materials. Bamboo has a tensile strength similar to that of steel making it very durable, but also heavier than other wooden boards of the same size.

• A wooden floor board with legs is the most traditional, elegant and expensive of all boards. These boards were used in historical times in Japan where one would sit on tatami mats and play, and are still used for important tournament games in Asia. Chinese versions of floor boards are not always made from a single block of wood, and more closely resemble a small table with an inlaid go board. The legs raise the board to the correct height. The board can range from 14-21?cm high, the thicker the more elegant. The underside often has a square recess (called a heso) to stop the wood from warping and to amplify the clicking sound of the stones hitting the surface. The best boards are made from Miyazaki kaya, which is rare. These are classified according to the quality of the wood grain. Itame refers to a bent or irregular grain; masame refers to consistent grain that runs straight across the top of the board. Masame boards are further classified as tenmasa (the top grain is straight, but grain along the cut end is curved, as in the illustration), and most-prized tenchimasa (grain is straight along the cut end as well as on top.) Prices of kaya boards range from $1,000 to $20,000 plus. Boards made of other woods, such as Alaskan spruce, Agathis or katsura are cheaper, around $500 to $2,000. The best boards are made in Japan, followed by Korea, which has good substitutes to kaya. China makes more economical ones out of cherrywood or bamboo.