NBA Basketball Size: Official Dimensions (Men, Women, NCAA)

TL;DR: Official NBA basketball size is 29.5 inches (75 cm) in circumference, weighing about 22 oz (624 g) - the standard men's "Size 7." WNBA and NCAA Women's basketballs are smaller at 28.5 inches (72 cm), Size 6. Junior sizes scale down to 27.5 in (Size 5) and below.

Official NBA basketball on hardwood court

Official NBA basketball size (men's pro)

The NBA's official game ball, manufactured by Wilson since 2021 (Spalding before that), is exactly 29.5 inches in circumference - just under 9.5 inches in diameter. It weighs 22 ounces (about 624 grams), slightly heavier than recreational balls so it has predictable bounce on regulation hardwood.

Circumference: 29.5 in / 75 cm
Diameter: ~9.39 in / 23.8 cm
Weight: 22 oz / 624 g
Size category: Size 7 (men's regulation)
Pressure: 7.5 to 8.5 psi when inflated

This is the same specification used by FIBA for senior men's competition, so an NBA-spec ball is also a FIBA-spec ball at the men's level (with minor cover-material differences).

WNBA and NCAA Women's basketball size

Women's pro and college basketballs are deliberately smaller: 28.5 inches (72 cm) circumference, ~20 oz (567 g). This is "Size 6." The smaller ball pairs with the women's game's faster perimeter play and was standardized to fit hand-span averages.

Basketball size comparison

Circumference: 28.5 in / 72 cm
Diameter: ~9.07 in / 23 cm
Weight: 20 oz / 567 g
Size category: Size 6

WNBA, NCAA Women's, and most international women's leagues all use this size. NCAA Women's court dimensions match the men's 94' x 50' court even though the ball is smaller.

Is the NCAA Men's basketball the same size as the NBA?

Yes - NCAA Men's regulation basketballs are 29.5 in (Size 7), identical to the NBA. The only visible difference is branding and panel design. The same is true at the high-school men's varsity level.

Youth and junior basketball sizes

Youth basketball is graded by age, with smaller circumference balls for smaller hands:

Youth basketball player

Size 7 (29.5 in): Men 15+, NBA, NCAA Men's, high-school varsity
Size 6 (28.5 in): Women 12+, WNBA, NCAA Women's, boys 12-14
Size 5 (27.5 in): Youth 9-11
Size 4 (25.5 in): Youth 5-8
Size 3 (22 in): Mini / under-5 / training

FIBA vs NBA: are the balls really the same?

Officially: yes, the men's circumference and weight match between FIBA and the NBA. In practice the cover material and seam construction differ - FIBA uses a synthetic leather composite while the NBA's Wilson ball uses a specific 8-panel composite leather design. Read more on FIBA vs NBA rule differences.

How to choose the right basketball size

Three quick rules:

Match the ball to the player's age and league. A 10-year-old shooting with a Size 7 ball develops form problems that take years to fix.
Match the surface to the ball. A leather indoor ball will get destroyed on an asphalt outdoor court. Use a composite or rubber outdoor ball outside, and save the leather ball for the gym.
Buy quality once. A regulation -80 ball will outlast three mall balls and shoot more consistently.

Get custom basketballs at any regulation size

Need branded basketballs for a team, school, or league? Hoopsbasket ships custom basketballs in five hybrid indoor-outdoor models with your team logo and colors printed on the panels. Start with Model 1 (Size 7, 29.5 in) for men's regulation use or Model 5 for outdoor durability. Minimum order is 100 units - ideal for clubs, AAU programs, schools, and tournaments.

For training tools that pair with regulation-size balls, browse our basketball training equipment collection.