Shoe size

A shoe size is a numerical indication of the fitting size of a shoe for a person. Several different shoe-size systems are still used today worldwide. In some regions, it is even customary to use different shoe-size systems for different types of shoes (e.g., men's, women's, children's, sport or safety shoes).

Foot length versus shoe length

The length of a foot is commonly defined as the horizontal distance between two parallel lines that are perpendicular to the foot and in contact with the most prominent toe and the most prominent part of the heel. Foot length is measured with the subject standing barefoot and the weight of the body equally distributed on both feet.

The size of the left and right foot is often slightly different for many people. In order to chose a shoe size, both feet should be measured and then the shoe size should be chosen based on the larger foot.

Each shoe is suitable for a small interval of foot lengths. The length of the inner cavity of a shoe must typically be 15–20 mm longer than the length of the foot, but this relation varies between different types of shoes.

There are three characteristic lengths that a shoe-size system can refer to:

• The average length of foot for which a shoe is suitable. For customers, this measure has the advantage of being directly related to their feet. It applies equally to any type, form, or material of shoe. However, this measure is less popular with manufacturers, as it requires them to test carefully for each new shoe model, for which range of foot sizes it is recommendable. It puts on the manufacturer the burden of ensuring that the shoe will fit a foot of a given length.
• The length of the inner cavity of the shoe. This measure has the advantage that it can be measured easily on the finished product. However, it will vary with manufacturing tolerances and provides the customer only very crude information about the range of foot sizes for which the shoe is suitable.
• The length of the "last", the foot-shaped template over which the shoe is manufactured. This measure is the easiest one for the manufacturer to use, as it identifies only the tool used to produce the shoe. It makes no promise about manufacturing tolerances or for what size of foot the shoe is actually suitable. It leaves all responsibility and risk of chosing the correct size with the customer.

All these measures differ substantially from each other for the same shoe.

Length unit

The following length units are commonly used today to define shoe-size systems:

• Millimeter (mm)
• Centimeter (cm) = 10 mm
• Paris point = 2/3 cm = 6.67 mm
• Barleycorn = 1/3 inch = 8.47 mm

Traditional shoe sizes by country

Warning: Most of the shoe-size systems listed in this section are not formally standardized. The exact relationship between a labelled shoe size and the interval of foot lengths for which that shoe is suitable can vary substantially between different manufacturers. The following descriptions may only approximate the exact sizing systems used by individual manufacturers. Discrepancies and variations occur in particular if shoes manufactured according to one shoe-size system are labeled in another system. With this lack of standardisation, shoe sizes can even vary from one manufacturer (or brand) as the manufacturer may use multiple different factires around the world to produce a given style.

Continental Europe

In France, Germany, and most other European countries, the traditional shoe size is the length of the last, measured in Paris points. For shoe types where the last is 20 mm longer than the foot for which the shoe will fit:

     shoe size = (foot length + 20 mm) / 6.67 mm

Formal standards

Various national and international standards (ISO 9407) recommend a shoe-size system known as Mondopoint. It is based on the mean foot length for which the shoe is suitable, measured in millimeters. A Mondopoint shoe label can optionally also specify the width of the foot, again in millimeters.

European standard EN 13402 recommends instead that shoes should be labeled with the interval of foot lengths for which they are suitable, measured in centimeters.

Width or girth designators

Some manufacturers offer shoes of different width for the same foot length. Such shoes are then also labelled according to the width or girth of the widest part of the foot (typically measured directly behind the toes with the subject standing on both feet and wearing socks or hose).

In the Mondopoint system, the shoe size label can state in addition to the length also the width of the mean foot for which the shoe is suitable, both measured in millimeters.

A number of other ad-hoc notations for width or girth are also used. Examples include (each starting with the narrowest width):

• AAAA, AAA, AA, A, B, C, D, E, EE, EEE, EEEE
• 4A, 3A, 2A, A, B, C, D, E, 2E, 3E, 4E
• N, M, W

None of these designations are formally standardized. The exact foot width for which these sizes are suitable can vary significantly between manufacturers. The A-E width indicators used by some US and UK shoe manufacturers are typically based on the width of the foot, and common step sizes are 1/4 inch (6 mm) or 3/16 inch (5 mm).

Myths

The myth that a man's foot size is correlated to the size of his penis has been discredited in anthropometric studies.

It is a myth that the Foot (unit of length) (304.8 mm) is about the length of the average UK male foot. The average today is less than 270 mm and 90% of the population is within 20 mm of that. So very few men today have feet that are a foot long. Most are over 25 mm (1 in) shorter. In the past, the average length would have been less. If the unit of measurement were named the 'shoe' it might be more appropriate. The topic of this article and the conversion chart above show that shoe size varies quite a lot between individuals. Even within an individual, the length of footwear varies depending on the purpose (house slippers, walking boots). However, some people do have shoes that are about 305 mm long.

This article is available under the terms of the GNU Free Documentation License. Original article can be found here.