Standard size of basketball court

Pro (NBA), College, High School and Junior High School courts differ on overall size an layout, but the interior markings for the “Foul Line”, “The Key” and “The Backboard and Rim” are the same. The NBA court has a unique 3 point line (arc). College and High School Courts share the same 3 point line measurements.

Regulation Sizes-Official Measurements:

Court Size Overall:

NBA and College – 94 feet long and 50 feet wide

The Foul Line:

For all courts including the NBA, the “foul line” distance is 15 feet from the foul line to the front of the backboard

The Key:

Standard for all basketball courts, “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):

NBA – the 3 point arc is 22 feet to the center of the rim on the sides with a straight line extending out 16 feet 9 inches from the baseline. Past those points the line extends out 23 feet 9 inches from the center of the rim.

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.

source : http://www.sportsknowhow.com/basketball/dimensions/nba-basketball-court-dimensions.html