Basketball court dimensions vary in overall length and width. In many areas of the country, older high school gymnasiums in particular have smaller overall size and layout than regulation. Many of these same gyms have varying backboard designs and measurements.
Even though College and High School courts may differ on overall size, the interior markings for the “Foul Line”, “The Key”, and “The Backboard and Rim” are the same.
Court Size Overall:
The overall size of a High School Basketball court is typically 84 feet long and 50 feet wide. Some Junior High School court will measure 74 feet long and 42 feet wide.
The Foul Line:
For all courts the “foul line” distance is 15 feet from the foul line to the front of the backboard. The “foul line” is 18 feet 10 inches from the baseline.
“The key” (sometimes called “the lane”) is 12 feet wide. Regulation courts have the backboard extending out 4 feet over the baseline into the key. A 6 foot arc (half circle) extends from the foul line away from the basket to complete the key.
The 3 Point Line (Arc):
College and High School – the 3 point arc is 19 feet 9 inches, with a straight line extending out 5 feet 3 inches (63 inches) from the baseline.
The Backboard and Rim:
The regulation distance from the ground to the top of the rim is 10 feet for all levels of play. Regulation backboards are 6 feet wide (72 inches) by 42 inches tall. All basketball rims (hoops) are 18 inches in diameter. The inner square on the backboard is 24 inches wide by 18 inches tall.
All line markings on the floor are 2 inches wide and can vary in color.