NBA Basketball Size: Official Dimensions & Guidelines

By Sarah Miller · June 9, 2040

The official NBA basketball size is Size 7, with a circumference of 29.5 inches (74.9 cm) and a weight of approximately 22 ounces (624 grams). This standard applies to all professional male players in the National Basketball Association.

Understanding NBA Basketball Size Standards

The NBA mandates strict specifications for game balls to ensure consistency, performance, and fairness across all levels of professional play. The official ball used in NBA games is known as Size 7, which is the largest standard basketball size available.

Key Specifications of an NBA Basketball

Circumference: 29.5 inches (74.9 cm)
Diameter: Approximately 9.4 inches (24 cm)
Weight: 22 ounces (624 grams)
Material: Full-grain leather (official Spalding or Wilson game balls)
Size Designation: Size 7

Why Size 7 Is Used in the NBA

The Size 7 basketball was selected based on the average hand size and physical attributes of adult male professional athletes. Using a standardized ball ensures uniformity in handling, shooting mechanics, and passing accuracy during high-level competition.

Advantages of Standardization

Ensures fair and consistent gameplay
Allows manufacturers to optimize grip and bounce
Facilitates player development and skill transfer
Supports referee consistency in calling palming or carrying violations

NBA Ball vs. Other Competitive Sizes

While the NBA uses Size 7, other leagues and age groups use different sizes tailored to player physiology. Understanding these differences helps players transition between levels smoothly.

Basketball Level	Ball Size	Circumference (inches)	Weight (oz)	Recommended For
NBA Men's Game	Size 7	29.5	22	Men 14+ years, professionals
NCAA Men's	Size 7	29.5	22	College men
NBA WNBA	Size 6	28.5	20	Women professionals
NCAA Women's	Size 6	28.5	20	College women
Youth Boys (12–14)	Size 6	28.5	20	Middle school, younger teens
Youth Boys (9–11)	Size 5	27.5	17	Ages 9–11
Youth Girls (8–11)	Size 4	25.5	14	Ages 5–8

Table data source:1, 2

The data shows that the NBA uses the largest standard basketball, reflecting the physical demands of elite men’s basketball. The WNBA and NCAA women’s leagues use a slightly smaller ball (Size 6), which better suits average hand span and strength. Youth categories progressively scale down to support skill development and control.

Official NBA Game Ball Manufacturers

Since 2021, Wilson has been the official supplier of NBA game balls, taking over from Spalding, which held the contract for decades. Each ball is crafted from premium full-grain leather and undergoes rigorous testing for durability, grip, and bounce consistency.

Features of the Official NBA Game Ball

Made with composite leather for indoor hardwood performance
Inflated to 7.5–8.5 psi for optimal bounce
Features the NBA logo and Wilson branding
Approximately 100 balls are prepared per game for rotation and inspection

Frequently Asked Questions About NBA Basketball Size

What size basketball does the NBA use?

The NBA uses a Size 7 basketball, which has a circumference of 29.5 inches and weighs 22 ounces. This size is standard for all professional men’s games.

Is the NBA basketball bigger than college balls?

No, the NBA basketball is the same size as the NCAA men’s basketball—both are Size 7 with a 29.5-inch circumference. The only difference may be brand or texture.

Why doesn’t the NBA use a larger ball?

The current Size 7 ball balances control, shooting mechanics, and physical capability. A larger ball would hinder dribbling, passing, and shooting efficiency at the professional level.

Do women in the WNBA use the same size ball as the NBA?

No, the WNBA uses a Size 6 basketball, which is one inch smaller in circumference (28.5 inches) and lighter (20 oz) compared to the NBA’s Size 7.

Can I use an NBA-sized ball for youth training?

It’s not recommended for players under 14. Using a ball that’s too large can hinder skill development. Younger players should use age-appropriate sizes (Size 5 or 6) to build proper technique.