Basketball guide
Youth Basketball Size Chart
Youth basketball size by age: size 5 for ages 7-8, size 6 for ages 9-11 and girls 12-14, and size 7 for boys 12-14.
Short answer
Best next step
Check the table, then confirm the brand chart.
Step 1
Find the likely size range
Swipe the table left to see every column.
| Age / division | Ball size | Published rule note |
|---|---|---|
| Under age 7 | Ask the program | Not covered by the published NBA/USA Basketball competition bands. |
| Ages 7-8 | Size 5 / 27.5 in | Published youth competition standard. |
| Ages 9-11 | Size 6 / 28.5 in | Published youth competition standard. |
| Ages 12-14 girls | Size 6 / 28.5 in | Published youth competition standard. |
| Ages 12-14 boys | Size 7 / 29.5 in | Published youth competition standard. |
Source context: Based on NBA and USA Basketball youth competition standards. Ages below 7 and local programs may use different equipment; league rules remain final.
Basketball sizing for youth players is primarily determined by the league. Most recreational and competitive leagues assign ball size by age division, and those assignments can differ for boys and girls divisions at older age levels. The most important first step is confirming what ball size your child's league uses for games, since that determines what to practice with at home.
For home training, matching the game ball size reinforces the correct dribbling, passing, and shooting feel. The published NBA and USA Basketball bands begin at age 7. We do not present an ages 5-8 grouping as an official range; programs for younger children choose equipment locally. Confirm with the coach or program director before buying.
Editorial note
We use these guides to narrow the starting range. Before you buy, compare that range with the exact brand chart, hands-on fit checks, and current sport rules. Read more about how our sizing works.
Spot a range that looks off, or a league rule we should mention? Tell us — corrections make these guides better for every parent.
Step 2
Confirm the competition age band
- 1. Confirm the player's age for the league's current season and whether the program groups players by age, grade, or another local rule.
- 2. Use the published age band to identify the starting ball size, including the girls' and boys' split at ages 12-14.
- 3. Check the size printed on the ball and match the home-practice ball to the one the league uses in games.
Step 3
Validate the fit before you shop
Good reasons
When to move to the next basketball size
- The player enters the next published age band and the league uses that standard.
- A boys' player enters the ages 12-14 segment that uses size 7 under the published guidance.
- The local program confirms a different transition and identifies the game ball it will use.
Avoid these
Common mistakes
- Moving to a larger ball early because it looks more like an adult game ball.
- Assuming every 12-year-old uses the same size without checking the program's division rule.
- Practicing at home with a different size from the ball used in team practices and games.
Parent tip
Because gender is not always how leagues assign ball size, use your league's rulebook as the final answer.
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Use the range above as a starting point, then recheck the exact product's brand chart before ordering.
Compare ball picksFAQ
What size basketball do 12-year-olds use?
Under the NBA and USA Basketball youth guidelines, girls ages 12-14 use size 6 (28.5 inches) and boys ages 12-14 use size 7 (29.5 inches). Local leagues can modify the standard, so confirm the game ball before buying a practice ball.
When do boys move to a size 7 basketball?
The NBA and USA Basketball youth chart moves boys to size 7 for the ages 12-14 segment. Some local programs switch later, so practicing with the league's actual game size matters more than moving up early.
What size basketball does 12U use?
There is no single universal 12U answer. The NBA and USA Basketball age chart separates girls and boys at ages 12-14: size 6 for girls and size 7 for boys. Check whether your event uses age, grade, or a local equipment rule.
What is the difference between basketball sizes 5, 6, and 7?
Size 5 is 27.5 inches, size 6 is 28.5 inches, and size 7 is 29.5 inches in circumference. The extra inch changes grip and shooting mechanics, which is why home practice should match the game ball.
Provenance
Sources used for this sizing guide
We use the published NBA/USA Basketball age bands where they apply and label younger-player guidance as program-dependent.
NBA and USA Basketball
Governing bodySupports: Ball size by age; Basket height by age
Reviewed July 2026
Know your child's starting size before you shop.
Pick the sport and gear, then add the measurements that matter. You'll get a practical starting range, fit checks, and what to avoid.