If you’re asking, “which sports ball is the smallest,” the answer depends on whether you mean the smallest ball by its official diameter or the smallest commonly recognized sports ball. A regulation table tennis ball is 40 millimeters across. A regulation squash ball is also about 40 millimeters, and its permitted size range can go slightly below that. So there is no clear winner between the two by nominal size, though squash balls can be marginally smaller at the low end of their specification.
Golf balls are a little larger, with a minimum diameter of 42.67 millimeters. That makes table tennis and squash the best answers when comparing the standard balls used in familiar, organized sports. Here’s how the measurements compare and why the question needs a little context.
Table tennis and squash balls are the smallest common sports balls
The International Table Tennis Federation (ITTF) specifies a ball diameter of 40 millimeters. World Squash rules specify a diameter of 40 millimeters, with a permitted tolerance of 0.5 millimeters. In practical terms, both sports use balls that are roughly the same width, while a squash ball made at the smallest permitted diameter could be slightly smaller than a table tennis ball.
That difference is tiny: half a millimeter is about the thickness of a few sheets of paper. It’s also important not to confuse a specification range with a universal measurement. The exact diameter depends on the particular ball and where it falls within the rules’ tolerance.
Therefore, a careful short answer is that table tennis and squash share the smallest nominal ball size among widely played, standard ball sports. If you compare the smallest size allowed by their rules, squash has a slight edge. Calling either one the definitive smallest without explaining the comparison can be misleading.
How the smallest sports balls compare
| Sport | Ball diameter | What the measurement means |
|---|---|---|
| Squash | 40 mm, with a ±0.5 mm tolerance | Its permitted range extends slightly below 40 mm. |
| Table tennis | 40 mm | The ITTF rule specifies a nominal 40 mm diameter. |
| Golf | At least 42.67 mm | The rules set a minimum diameter, so a conforming ball may be larger. |
These figures come from the sports’ equipment rules, but they are not all expressed in precisely the same way. Squash has a stated tolerance around its nominal size, while golf’s rule gives a minimum. That makes the table useful for a general comparison, but not a measurement of every ball sold or used in practice.
Why table tennis balls look so small
A table tennis ball is only 4 centimeters wide, but its size works well with the sport’s equipment and playing area. Players use a small racket and a table rather than a full-size court, and rallies depend on controlling the ball’s speed, spin, and bounce over a short distance.
The ITTF also specifies a ball weight of 2.7 grams. That low weight contributes to the way a table tennis ball responds to a racket stroke and air movement. It can travel quickly, but spin and placement are central to how players control it. Diameter alone doesn’t explain how the ball behaves; its material, construction, weight, and the surface it meets also matter.
Older table tennis balls were not always the same size as the modern standard. The sport’s ball size changed over time, so older equipment guides or recollections may describe a smaller ball. For current comparisons, it’s best to use the present rules rather than assume every table tennis ball across the sport’s history was 40 millimeters.
Why squash balls are a similar size but feel different
A squash ball is close to the same diameter as a table tennis ball, but the two are made for very different games. Squash balls are rubber, and their bounce depends on the ball type and how warm it becomes during play. Players typically warm the ball by hitting it repeatedly, which helps it reach the bounce needed for a rally.
Squash balls are commonly marked with colored dots to indicate different playing characteristics. The markings help players choose a ball suited to their experience and conditions. The small diameter doesn’t mean a squash ball behaves like a lightweight plastic table tennis ball: its material, mass, and bounce are quite different.
This is why “smallest” is only one way to compare sports equipment. A ball’s diameter tells you how wide it is, but it doesn’t tell you how heavy it feels, how high it bounces, or how it moves through the air.
Is a golf ball the smallest sports ball?
Golf balls are often mentioned in this conversation because they look small next to balls used in sports such as basketball, soccer, or volleyball. But by diameter, a regulation golf ball is larger than a table tennis or squash ball. The Rules of Golf require a ball to be at least 42.67 millimeters in diameter.
The wording matters: 42.67 millimeters is a minimum, not a claim that every golf ball measures exactly that size. Still, it provides a useful reference point. Compared with a 40-millimeter table tennis ball, even the minimum permitted golf ball is larger.
Golf balls also feel much denser and heavier than table tennis balls. That can make a golf ball seem small and substantial at the same time. If you’re comparing only diameter, however, the smaller size belongs to squash and table tennis.
What “smallest” means in a sports-ball comparison
There isn’t a single answer unless you define what counts as a sports ball. A comparison of standardized equipment in popular sports is straightforward: table tennis and squash balls are both nominally around 40 millimeters in diameter. A comparison of every ball used in every sport, informal game, or specialized discipline is much harder. Some activities use unusual equipment or have different rule systems, so a broad claim about every sport would need a carefully defined list.
It also helps to distinguish between a ball’s diameter and its overall size in other senses. One ball may be narrower but heavier; another may have a smaller volume but a different shape or construction. For regulation equipment, diameter is usually the clearest way to answer a question about which ball is physically smallest.
When checking a specific ball, look for the rules of the sport’s governing body and the equipment’s intended level of play. A recreational ball may not have the same specifications as one approved for competition. The product label or manufacturer’s documentation can clarify whether it is intended to meet official rules.
Frequently asked questions
Is a table tennis ball smaller than a squash ball?
Both have a nominal diameter of 40 millimeters. Squash rules allow a tolerance of 0.5 millimeters, so a squash ball at the smallest end of its permitted range can be slightly smaller. The answer depends on the individual ball’s measurement.
Is a golf ball smaller than a table tennis ball?
No. A regulation golf ball must be at least 42.67 millimeters in diameter, compared with the 40-millimeter nominal diameter of a table tennis ball.
What is the diameter of a regulation table tennis ball?
The ITTF specifies a diameter of 40 millimeters for a table tennis ball. Its rules also specify a weight of 2.7 grams.
What is the diameter of a regulation squash ball?
World Squash rules specify a nominal diameter of 40 millimeters, with a tolerance of 0.5 millimeters. The actual diameter can therefore vary within that permitted range.
Does the smallest ball always belong to the fastest sport?
No. Ball size by itself doesn’t determine how fast a sport is. The ball’s weight, material, aerodynamics, playing surface, and how athletes strike or throw it all affect its movement.
Does a smaller ball mean it is lighter?
Not necessarily. Diameter measures width, not weight. Materials and construction matter, so balls with similar diameters can have very different masses and playing characteristics.
Conclusion
For a simple, accurate answer, squash and table tennis use the smallest standard balls among familiar ball sports, at about 40 millimeters in diameter. Their nominal sizes are the same, although the permitted squash-ball range can extend slightly smaller. A golf ball is larger, with a minimum diameter of 42.67 millimeters. So the best answer to “which sports ball is the smallest” is table tennis or squash, with the precise winner depending on the individual ball and how the comparison is made.