Tennis balls

Can, pack or case: how many balls do you need

A can of three or four balls is the standard purchase unit. Packs of several cans and cases are for those who play every week, for schools, or for clubs.

One fact that sets the rest in order: the rules do not measure the life of a ball in weeks, they measure it in games. The test with which the ITF approves a model simulates nine games of match play. In a tournament, how many balls are used, two, three, four, or six, and how often they are changed is announced by the organizer in advance; the rules do not specify it.

Most of our catalog comes in cans. Above that are packs, cases of dozens of cans, large boxes, and buckets of practice balls. The rule for deciding is simple: a can starts to lose pressure as soon as it is opened, so a case is only worth it if you are going to use it up within a reasonable timeframe.

How long does a tennis ball last?

There is no published timeframe: no manufacturer, neither Wilson, nor Head, nor Dunlop, nor Babolat, publishes how long a can lasts once opened.

What is known is the mechanism, and they are two different things that go in opposite directions:

• Stored, the ball loses air little by little through the rubber and bounces less. It is the dead ball at the bottom of the closet.
• Played, what wears out is the felt. The ball loses mass and stiffness, and then it bounces higher and flies differently.

That is why "a used ball bounces less" is not always true: it depends on whether it died in the closet or on the court.

And a measurement that changes intuition. A study published in Sports Engineering counted the impacts that a ball receives in nine games of professional tennis: between 82 on grass and 107 on clay, and around 105 on hard court. The durability test with which the ITF approves that same ball applies 20. The laboratory falls short by about five times compared to what happens on a real court. So the approval seal does not tell you how long a ball is going to last for you on your court.

All court, clay court, extra duty: what is on the can

All those words say the same thing in two languages: what surface the felt is designed for. All court and extra duty point to the hard court; clay court and regular duty, to clay and indoor.

The equivalence between the two nomenclatures is not fixed by any organization: it is industry usage. In Europe, brands usually label all court and clay court; in the Anglo-Saxon market, extra duty and regular duty. In our own catalog, both coexist: the Wilson Championship comes marked as extra duty and the Dunlop Fort as all court.

And there is one more layer, that of the rules, which goes exactly the opposite of what it seems. The ITF defines three types of balls, and the fast one is recommended for slow courts, the Type 1, for clay, while the slow one is for fast courts, the Type 3, for grass. It is compensatory. Type 3 is also the only larger one, 7.00 to 7.30 centimeters compared to the normal 6.54-6.86.

The real difference is in the felt. Wilson describes extra duty as a thicker felt with a more open weave, made to withstand the friction of the hard court. On clay, that same felt picks up dirt and the ball becomes spongy; on hard court, a fine felt peels sooner. How much life you lose by using the one that doesn't match no one has published, so treat it as a preference, not as a defect.

Starter balls: red, orange, and green

They are slower balls so that a child can play ball from the first day, and they are defined by the ITF rules: red (stage 3), orange (stage 2), and green (stage 1).

Red is the first: larger than the adult one, bounces less, and is the only one that can be made of foam. Orange is the intermediate stage, and green is already a yellow ball with a green dot. The diameter and bounce of each one are in our tennis ball size guide.

Two clarifications about the rule. What the ITF prohibits in under-10 competition is not "the yellow ball", it is the standard ball: the green one is yellow. And the percentages 75%, 50%, and 25% come from a Tennis10s program manual, not from the rules, and they talk about a slower ball, not less compression.

The ITF associates each stage with an age and a court: red up to 8 years on a reduced court, orange from 8 to 10 on an intermediate court, and green for the 9 and 10 year olds who are more advanced, already on a full court. They are recommendations for competition, not obligations for playing on a Saturday.

What does ITF approval guarantee?

That the ball meets the measurements and bounce of the rules, and nothing else. The ITF itself writes it bluntly: the approval "does not imply any other form of approval or endorsement". It is not a seal of quality or durability.

Behind the seal there is control, and that is no small thing. To approve a model, the brand sends samples to the ITF technical center in London, the only place where they can be tested, and pays a fee for each type of ball. In addition, the ITF takes random samples from the market and tests them again: accumulating failures gets a yellow card, and a second yellow card removes the approval of the model for twelve months.

And one thing you do not need: outside of a tournament you are not obliged to anything. An unapproved ball is perfectly legal for playing with a friend.

Complete your equipment

If you are going to renew something else, you have tennis rackets, tennis shoes, tennis overgrips, strings, racket bags, and vibration dampeners. And if what you are looking for are padel balls, they are in their own section: they weigh the same, but they are not the same ball.

Doubts between a can and a case? Write to us and we will tell you which one is worth it for you.

Guide updated in September 2026.