A basketball's size is chosen by age and gender, not by how hard you shoot — size 7 for men and boys from age 12-14 up, size 6 for women, size 5 for children up to 12. Everything else comes down to where you actually play: a ball built for a wooden court wears out fast outdoors, and an outdoor ball behaves differently indoors than you might expect. Below are the exact numbers, plus the quick test worth running before you buy — new or secondhand.
Size depends on age and gender, not how hard you shoot
| Size | Circumference | Weight | Who it's for |
|---|---|---|---|
| 7 | 74.9–78 cm | 567–650 g | men and boys from age 12-14 up, men's competition |
| 6 | 72.4–73.7 cm | 510–567 g | women and boys aged 12-14 |
| 5 | 69–71 cm | 470–510 g | children up to 12 |
| 3 | 56–58 cm | 300–330 g | youngest players, for technique work |
A standard basketball has a 24 cm diameter, a circumference of 75 to 76 cm, and weighs between 0.57 and 0.62 kg — those are the size 7 numbers, the ball used in men's competition. A bigger ball does not help anyone score more often; if anything, the bigger the ball, the harder it is to get it through the hoop, which is why children play with a genuinely smaller ball rather than just one that happens to fit smaller hands.
Indoor, outdoor, or both — where the material choice starts
The first real decision, before anything else, is where you actually play.
Natural leather. The premium material, used for competition balls in the NBA and EuroLeague. It performs beautifully on a wooden court but breaks down fast outdoors — a so-called "hernia" appears, a bulge that deforms the ball permanently. There is little point buying one if you mostly play outside.
Synthetic (composite) leather. The alternative that holds up almost as well as natural leather, costs less, and copes a little better with mixed conditions. The sensible choice for someone who plays mostly indoors but heads outside occasionally.
Rubber. The cheapest and most durable material for hard surfaces — asphalt, concrete, cement. It works indoors too, though grip is somewhat weaker than a leather ball's. The standard choice for anyone playing exclusively outdoors.
The label on the box tells you exactly what you are buying: Indoor means built for a wooden court, Outdoor means built for hard surfaces, and Indoor/Outdoor is a universal compromise — decent everywhere, excellent nowhere. Some balls carry an All Surface label instead, promising the same performance on any court — in practice, the same compromise stated more boldly. A ball marked Indoor only, played outdoors for a couple of weeks, risks that same hernia.
The one-minute test before you pay
Correct basketball pressure sits between 0.48 and 0.61 atmospheres. Few people carry a gauge, but there is a simple test: hold the ball at head height, roughly 180 cm up, and let it drop without pushing it. A correctly inflated ball bounces back to about waist height — 120 to 140 cm. A much lower bounce means it needs air. A bounce nearly as high as the drop point means it is overinflated, and control suffers for it.
The rest of the check is done by hand, not by eye. Run your palm over the whole surface, pressing gently — an early hernia feels like a small bump under the material, one that is hard to spot just by looking in the first few weeks. Check the grooves and the valve area for cracks too; a new ball should have none. The grooves themselves do double duty — they improve grip in the hand and hold the ball's structure together, which is why their width is strictly regulated in competition, capped at 6.35 mm. A standard ball has eight bonded panels; some models use twelve, with no effect on the rules of play.
Pressure does not stay constant over time. A ball left unused for a few weeks naturally loses air, especially in winter, when cold contracts the rubber inside. The bounce test is worth repeating periodically, not just at purchase — a ball losing air gradually changes how your dribble feels before you consciously notice why.
Buy for where you play, not for the brand on the box
Known brands — Spalding, Molten, Wilson, Nike — differ from each other less than it seems, and the real difference stays where this article puts it: material and size. The most common mistake with a first basketball is not picking the wrong brand, it's picking a material wrong for where the ball actually gets played — a leather ball bought for a courtyard court, warped within a month, or a rubber ball carried indoors, where its grip always trails a leather ball's.
The same checks apply to a secondhand ball without changes — the bounce test and the palm check for hernias don't care whether the ball is new. Worth adding one thing: look at the grooves themselves. Since they're what holds the grip in your hand, visibly worn-down grooves are worth pausing over even if the bounce test comes back fine.
Basketball's near-universal orange color is not an accident — it was chosen for maximum contrast on court, so players and spectators could track a ball moving quickly from side to side. Balls in other colors exist today, but orange remains the standard on any competition court.
Sporta MD covers football, basketball, volleyball and tennis. The right size and material matter more than the brand on the box — everything else comes down to where you play.