The key, free throw lane or shaded lane refers to the usually painted area beneath the basket; for the NBA it is 16 feet (4.9 m) wide, for the NCAA it is 12 feet (3.7 m) wide; for both instances it extends 15 feet (4.6 m) from the backboard. At the top of the rectangle is the free throw line, behind which players shoot uncontested shots when they 're fouled. A circle is drawn around the free - throw line with a 6 feet (1.8 m) radius; this is used for jump ball instances, as is done at the center circle. Two 6 - inch hash lines, 3 ft from the free throw lane line and 5 ft 8 in from the free throw line, show the lower defensive box linked to the restricted area.
where is the free throw line measured from
15 feet (4.6 m) from the backboard