USA Basketball recommends size 5 for ages 7–8, size 6 for ages 9–11, and size 6 for girls and size 7 for boys ages 12–14; grades 9–12 follow the same size 6/7 division. Circumferences are 27.5, 28.5 and 29.5 inches. Size 4 and 3 labels vary by maker and youth program, so verify local rules.
Ball size should follow the league first. USA Basketball’s age guidelines recommend a size 5 ball for ages 7–8, size 6 for ages 9–11, and size 6 for girls and size 7 for boys ages 12–14. The grades 9–12 guidance uses the same size 6/7 division.
USA Basketball youth guidance
| Player group | Recommended size | Circumference |
|---|---|---|
| Ages 7–8, boys and girls | 5 | 27.5 in |
| Ages 9–11, boys and girls | 6 | 28.5 in |
| Ages 12–14, girls | 6 | 28.5 in |
| Ages 12–14, boys | 7 | 29.5 in |
| Grades 9–12, girls | 6 | 28.5 in |
| Grades 9–12, boys | 7 | 29.5 in |
USA Basketball lists size 7 as 29.5 inches, size 6 as 28.5 inches and size 5 as 27.5 inches. Size 4 and size 3 balls are commonly sold for younger recreation and skills practice, but the age label is manufacturer-specific rather than part of that USA Basketball table.
Confirm the rule for your league
School, club and tournament rules can use age, grade or competition-specific classifications. Check the event rulebook before buying. The USA Basketball Youth Guidelines are a recommendation framework, not a replacement for a local league’s rule.
Choose the court cover
After ball size, choose a ball rated for the surface. Compare leather and composite indoor balls or review indoor vs outdoor basketballs. For younger players, also confirm the rim height allowed by the league and use an adjustable portable hoop only according to its manual.
Sources: USA Basketball Youth Guidelines, Spalding size guide.
Common questions
What size basketball does USA Basketball recommend for a 10 year old?
Size 6 (28.5 inches) for ages 9–11 under USA Basketball’s youth guidelines. Check the league rule too.
What size basketball for ages 7 to 8?
USA Basketball recommends size 5 (27.5 inches) for ages 7–8.
What size ball do girls and boys ages 12 to 14 use?
USA Basketball recommends size 6 for girls and size 7 for boys ages 12–14; local competitions can differ.
Are size 3 and size 4 basketballs assigned to one age group?
Not by the USA Basketball youth table. These smaller recreational sizes vary by manufacturer and program.