Question: are all basketball rims the same size?
Answer: For junior high, high school, NCAA, WNBA, NBA and FIBA, the rim is exactly 10 feet off the ground. Rims at every level of play are 18 inches in diameter. Backboards are also the same size at each of these levels. A regulation backboard measures 6 feet wide and 42 inches (3.5 feet) tall.