Per NBA regulations, the dimensions of a basketball backboard are 6 feet wide by 3 ½ feet high. The backboard is marked with a 2-inch white rectangle that is centered behind the ring; the rectangle's outer dimensions are 24 inches wide by 18 inches high. The basket itself consists of a metal ring with an 18-inch inner diameter and a white cord net that is 15 to 18 inches long.
Other sport governing bodies have different regulations for basketball equipment. In the NCAA, for example, the backboard must be 6 feet wide, but it can be 3 ½ or 4 feet high. The NCAA recommends that replacement and newly installed backboards be 3 ½ feet high, however.