There are two official pool table sizes: 9-foot and 8-foot. The dimensions of a 9-foot table's playing surface must be 100 by 50 inches, while the dimensions of an 8-foot table's surface must be 92 by 46 inches.
The playing surface is required to be rectangular and symmetrical. Regardless of playing surface size, a pool table must be between 29 1/4 and 31 inches to be within regulation. A table's rail width must be between 4 and 7 1/2 inches. These dimension requirements are only necessary for events run or sanctioned by the World Pool-Billiard Association; tables made for home use need not meet the association's standards. Additionally, the World Pool-Billiard Association can sanction the use of non-standard tables in tournaments at its discretion.