How Long Is a Football in Centimeters? Size Guide

Key points for measuring a football

Identify the ball type. This answer is for an association football (soccer ball), not an American football or rugby ball.
Check the size marking. A full-size adult match ball is normally size 5; smaller sizes are made for younger players and practice.
Measure diameter across the ball. Put a ruler or tape through the center, from one outer side to the other, at the widest point.
Measure circumference around it. Wrap a flexible tape around the ball’s broadest part; a size 5 ball is about 69–71 cm around.
Compare like with like. Inflation, shape, and measurement technique can affect a home measurement, so use the official size range rather than expecting every ball to show one exact number.

What the size 5 measurement means

For the standard adult association football, the clearest answer to “How long is a football in centimeters?” is its diameter: approximately 22–23 cm for a size 5 ball. A sphere does not have a single natural “length” in the way a ruler or stick does, so people may mean either the distance across the ball or the distance all the way around it.

These are different measurements. Diameter runs straight through the center from one side to the other. Circumference follows the curved surface around the ball. For a regulation size 5 match ball, the circumference is 68–70 cm under the IFAB Laws of the Game. That range corresponds to a diameter of roughly 21.6–22.3 cm, because circumference divided by pi gives the diameter. Rounded everyday descriptions commonly call this about 22–23 cm across.

The rules specify circumference, not a separate “length.” A ball can also look slightly different depending on its panel design, but its overall shape should be spherical. The seam pattern is not a reliable way to judge its size.

How football sizes compare

Size numbers distinguish balls intended for different ages and uses. Size 5 is the familiar full-size ball used for adult matches and many older youth groups. Smaller balls are easier for younger players to handle, but exact recommendations vary by competition and local rules.

Size 5: The standard full-size ball. Its circumference is 68–70 cm, giving a diameter of roughly 22 cm.
Size 4: Smaller than size 5 and commonly used in youth football. Its circumference is generally around 63.5–66 cm, or about 20–21 cm in diameter.
Size 3: A smaller ball often used for younger children and introductory play. Its circumference is generally around 58.5–61 cm, or about 19 cm across.

These size 3 and 4 figures are common size ranges, not a claim that every manufacturer or competition uses exactly the same specification. Check the ball label and the relevant competition’s rules when the precise size matters.

Everyday comparisons for scale

A diameter of about 22 cm is close to the width of a sheet of A4 paper, which is 21 cm. Place a size 5 ball beside the short edge of A4 paper and it will be a little wider than that edge. It is also roughly the width of a typical dinner plate, though plates vary considerably, so this is a visual comparison rather than a measurement standard.

Another useful comparison is a standard 30 cm ruler: a size 5 ball is a little under three-quarters of that ruler’s length across. Its circumference, about 69–70 cm, is longer than two such rulers laid end to end. These comparisons help distinguish the ball’s width from the much larger number you get by wrapping a tape around it.

Household objects are not perfect measuring tools. A plate’s diameter, for example, can vary by several centimeters between designs. Use a ruler or flexible tape for an actual measurement.

How to measure one accurately

To check a football at home, use a flexible measuring tape for circumference or a straight ruler for diameter. Measure the ball when it is properly inflated and sitting in a round shape. A soft, underinflated ball may flatten where it rests, while an overinflated one may become unusually firm or distorted; either can make a casual measurement misleading.

For diameter, align the ruler across the widest part and pass through the center. If you cannot see the center, rotate the ball and check more than one direction.
For circumference, wrap the tape around the widest part without pulling it tight enough to compress the surface.
If using string, mark where it completes one full loop, then straighten the string and measure between the marks.

Do not measure only one panel or the distance between seams. Those are parts of the covering, not the ball’s overall diameter or circumference. A tape angled across the surface rather than around the middle can also give an inaccurate circumference.

Common misconceptions and what to check first

The most common confusion is treating “length,” “diameter,” and “circumference” as interchangeable. For a spherical soccer ball, diameter is the across-the-middle measurement; circumference is the loop around it. If someone asks how long a football is without giving a measurement method, clarify which one they mean.

Another source of confusion is the phrase “football.” In many countries it means association football, or soccer. In the United States, it often means American football, an oval ball with a different shape and different measurements. Rugby balls are oval too. The 22–23 cm answer here applies to a size 5 association football, not those other sports.

Before deciding that a ball is the wrong size, check its printed size, its intended age group, whether it is properly inflated, and whether you measured across the center. A size 4 ball will naturally be smaller than a size 5, and a ball designed for casual play may not meet a particular match specification.

Frequently Asked Questions

How many centimeters is a size 5 football?

A size 5 association football has a circumference of 68–70 cm under the IFAB Laws of the Game. That is roughly 22 cm in diameter; everyday descriptions often round the diameter to 22–23 cm.

Is a football 22 cm long or 70 cm long?

Both can describe the same ball, but they refer to different measurements. About 22 cm is the diameter across the center, while 68–70 cm is the circumference around the outside.

How do I know whether my football is size 5?

Look for the size printed on the ball or its label, then check the circumference if you need to verify it. A size 5 match ball should measure 68–70 cm around when measured across its widest part.

Are all footballs the same size?

No. Association footballs come in different numbered sizes, including smaller sizes for younger players and practice. American footballs and rugby balls are different sports equipment and are not measured by the soccer-ball size 5 standard.

Does inflation change a football’s size?

Inflation can affect the ball’s shape and measurement. For a fair check, inflate it according to the pressure guidance printed by its maker, then measure around the widest part without squeezing it.

Sources: The IFAB Laws of the Game. Menus and buttons can differ slightly by version. Spotted something out of date? Tell us.