How Big Is an NBA Basketball? Full Size & Specs

By Sarah Miller · March 19, 2044

An NBA basketball has a standard circumference of 29.5 inches (74.9 cm) and a diameter of approximately 9.4 inches (23.9 cm). This size, known as Size 7, is used by all professional players in official games.

Understanding NBA Basketball Dimensions

The size of an NBA basketball is strictly regulated to ensure consistency across all games. The official ball must meet precise specifications set by the National Basketball Association (NBA) for professional play.

Key Measurements of an NBA Basketball

Circumference: 29.5 inches (74.9 cm)
Diameter: Approximately 9.4 inches (23.9 cm)
Weight: 22 ounces (624 grams)
Size Designation: Size 7
Material: Leather composite cover for indoor performance

Comparison Across Leagues and Levels

Basketball sizes vary depending on the league, gender, and age group. While the NBA uses a standardized ball, other organizations like FIBA, WNBA, NCAA, and youth leagues have different requirements.

League/Level	Ball Size	Circumference (inches)	Diameter (inches)	Weight (oz)
NBA	Size 7	29.5	9.4	22
WNBA	Size 6	28.5	9.0	20
FIBA	Size 7	29.5	9.4	22
NCAA Men	Size 7	29.5	9.4	22
NCAA Women	Size 6	28.5	9.0	20
Youth (Ages 9-12)	Size 6 or 5	27.5–28.5	8.7–9.0	17–20
Mini Ball (Kids)	Size 3	7.0	10

Table data source:1, 2, 3

The data shows that the NBA, FIBA, and NCAA men’s basketballs are identical in size and weight, ensuring global consistency at elite levels. The WNBA and NCAA women’s balls are slightly smaller and lighter, improving handling and shooting mechanics for average hand size. Youth sizes scale down further to support skill development.

Materials and Construction of NBA Balls

Since 2021, the NBA has partnered with Wilson to supply game balls, replacing Spalding after decades. These balls are made from premium composite leather designed for optimal grip, bounce, and durability on hardwood courts.

Features of Official NBA Game Balls

Made with 8-panel construction for balanced handling
Inflated to between 7.5 and 8.5 psi for regulation bounce
Textured surface enhances control during fast-paced play
Consistent weight distribution for accurate shooting

Why Ball Size Matters in Performance

The exact dimensions of a basketball influence dribbling, passing, and shooting accuracy. A ball that is too large or heavy can reduce control, especially for players with smaller hands.

Larger balls improve finger spread and shooting stability
Proper circumference ensures secure grip during crossovers and drives
Standardized weight allows consistent shot arc and release timing
Uniform size enables fair competition and predictable ball behavior

Frequently Asked Questions About NBA Basketball Size

How big is an NBA basketball in inches?

An NBA basketball has a circumference of 29.5 inches and a diameter of about 9.4 inches.

What is the weight of a regulation NBA basketball?

A regulation NBA basketball weighs 22 ounces (624 grams).

Is the NBA ball bigger than the college ball?

No, the NCAA men’s basketball is the same size as the NBA ball—29.5 inches in circumference and 22 ounces in weight.

Do women’s professional leagues use a smaller ball?

Yes, the WNBA uses a Size 6 ball with a 28.5-inch circumference and 20-ounce weight, making it easier to handle for most female athletes.

When did the NBA switch to Wilson basketballs?

The NBA switched from Spalding to Wilson as its official game ball supplier starting in the 2021-2022 season.

In summary, the NBA basketball is precisely engineered to balance performance, consistency, and player comfort. With a 29.5-inch circumference and 22-ounce weight, it remains the gold standard for professional men's basketball worldwide.