Basketball size by age: a sourced coach and parent chart

Read the chart and check the league

A label such as “junior” or “youth” can mean different things across brands. Compare the numbered size and stated circumference instead. If a product listing leaves either out, don't guess from a photograph. Ask for the exact model and variant specification.

The age is the program's playing category, not a judgment about an individual child. A school grade does not always map neatly to one age. Ask the organizer which category and equipment rule applies rather than collecting personal details on a website.

Ball size, circumference and age guidance

The source figures are in inches. For a unit conversion, multiply by 2.54 centimetres per inch. Size 5's 27.5 inches converts to 69.85 centimetres. A maker may describe a nominal size with its own permitted manufacturing range; that is not a reason to replace the competition's stated size.

Source-specific boys and girls guidance

Keep the age and category together when reading the 12-to-14 row. It does not say that all children of that age use a size 7 ball. Likewise, don't move the size 6 row down to a younger age simply because the ball is in stock. The local organizer's rule is the fact you need to resolve.

For a teaching session outside competition, observe whether the ball can be held and passed with control. This is an editorial coaching check, not a new equipment standard. A player who is struggling may need a shorter passing distance or a different task. Changing equipment should be discussed with the program, rather than described as a guaranteed fix.

Surface and material considerations

The playing surface is a separate buying question from size. Check the maker's intended indoor or outdoor use for the exact ball. A size label does not tell you whether its cover is intended for rough pavement. Don't infer a model's suitability from a generic photo of a gym.

Choose the next step for the required size

• Size 5 or 6: keep the required circumference beside the model name when checking an offer. Spalding’s Zi/O Excel specifications list a 28.5-inch family option, but that does not identify a verified size-6 Amazon offer here. Use an existing correct ball until the selected item’s size is clear.
• Size 7, outdoor or mixed venues: use the comparison below; its three linked variants are 29.5 inches.
• Size 7, indoor only: compare the indoor ball shortlist, also with 29.5-inch links.

Read care and inflation instructions on the actual ball or official product page. This guide supplies no universal pressure because different balls can have different marked ranges. Store equipment as directed and check for damage before use. A heavily worn or misshapen ball can make a size comparison less useful.

For a household with more than one age group, avoid a single “family size” claim. One program may require a different ball from another. Label equipment for the activity rather than with children's personal information. A plain equipment tag is enough to distinguish two otherwise similar balls.

For the rest of a practice kit, our training equipment comparison separates markers, return aids and ball storage by task. A correct ball size does not create a need to buy extra equipment.

When league rules differ

Write down the league age band and the ball size it calls for. Add the model you have. Some rules give the distance around the ball. Match that figure if there is no size number. If two sheets disagree, ask which one is in force.

At a shared practice, tell each adult which ball to use for their task. Keep the same ball while you watch a task. A change of ball can change the result. Note the task and ball you used. Do not rank children in public.

If you also need a fixed basket, the in-ground hoop comparison covers that separate space and installation decision. It does not change the ball size your league requires.

Use the right equipment category

The age/size facts come from the three NBA and USA Basketball youth charts. They are recommendations for their named categories. No preschool circumference or maker-specific pressure has been inferred. The chart is a reference, not a product shortlist or a claim of equipment testing.

FAQ

Does a size number prove a ball is right for this league?

Match the league’s current rule first. Check the ball’s stated size and distance around it against that rule. A youth label on packaging is not the league’s approval. Use the named chart as guidance while you wait for the organizer’s answer.

Should two groups share the same ball at every station?

Use the ball each task and local rule require. If groups use different balls, tell the adults which belongs at each station. Keep the same ball during an observation so a change in equipment is not mistaken for a change in control.