Shoe size
A shoe size is an indication of the fitting size of a shoe for a person. There are a number of different shoe-size systems used worldwide. While all shoe sizes use a number to indicate the length of the shoe, they differ in exactly what they measure, what unit of measurement they use, and where the size 0 (or 1) is positioned. Some systems also indicate the shoe width, sometimes also as a number, but in many cases by one or more letters. Some regions use different shoe-size systems for different types of shoes (e.g. men 's, women's, children's, sport, and safety shoes). This article sets out several complexities in the definition of shoe sizes. In practice, shoes should be tried on for size and fit before they are purchased. Deriving the shoe size. Foot versus shoe and last. The length of a person's foot is commonly defined as the 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 between both feet. The sizes of the left and right feet are often slightly different. In this case, both feet are measured, and purchasers of mass-produced shoes are advised to purchase a shoe size based on the larger foot, as most retailers do not sell pairs of shoes in non-matching sizes. Each size of shoe is considered suitable for a small interval of foot lengths, typically limited by half-point of the shoe size system. A shoe-size system can refer to three characteristic lengths: All these measures differ substantially from one another for the same shoe . For example, the inner cavity of a shoe must typically be 15 mm longer than the foot, and the shoe last would be 2 size points larger than the foot, but this varies between different types of shoes and the shoe size system used. The typical range lies between for the UK/US size system and for the European size system, but may extend to and . Length. Sizing systems also differ in the units of measurement they use. This also results in different increments between shoe sizes, because usually only "full" or "half" sizes are made. The following length units  are commonly used today to define shoe-size systems: Since early 2000s, labels on the sports shoes typically include sizes measured in all four systems: EU, UK, US, and CM (Mondopoint). Zero point. The sizing systems also place size 0 (or 1) at different locations: Width. Some systems also include the width of a foot (or the girth of a shoe last), but do so in a variety of ways: The width for which these sizes are suitable can vary significantly between manufacturers. The A–E width indicators used by most American, Canadian, and some British shoe manufacturers are typically  based on the width of the foot, and common step sizes are inch (4.8 mm). Difficulties. There could be differences between various shoe size tables from shoe makers and shoe stores. They are usually due to the following factors: Conversion tables available on the Web often contain obvious errors, not taking in to account different zero points or wiggle room. Although shoe size systems are not fully standardised, the ISO/TC 137 had released a technical specification ISO/TS 19407:2015 for converting shoe sizes across various local sizing systems. Even though problem of converting shoe sizes accurately has yet to  be fully resolved, this standard serves as "a good compromise solution" for shoe-buyers. Common sizing systems. United Kingdom. Shoe size in the United Kingdom, Ireland, India, Pakistan and South Africa is based on the length of the last used to make the shoes, measured in barleycorns ( inch) starting from the smallest size deemed practical, which is called size zero. It is not formally standardised. Note that the last is typically longer than the foot heel to toe length by to in or to 2 barleycorns, so to determine the shoe size based on actual foot length one must add  2 barleycorns. A child's size zero is equivalent to 4 inches (a hand = 12 barleycorns = 10.16 cm), and the sizes go up to size (measuring barleycorns, or ). Thus, the calculation for a children's shoe size in the UK is: equivalent to: An adult size one is then the next size up (26 barleycorns, or ) and each size up continues the progression in barleycorns. The calculation for an adult shoe size in the UK is thus: equivalent to: Although this sizing standard is nominally for both men and women, some manufacturers use different numbering for women's  UK sizing. In Australia and New Zealand, the UK system is followed for men and children's footwear. Women's footwear follows the US sizings. In Mexico, shoes are sized either according to the foot length they are intended to fit, in cm, or alternatively to another variation of the barleycorn system, with sizes calculated approximately as: equivalent to: United States. In the United States and Canada, the traditional system is similar to British but there are different zero points for children's, men's, and women's shoe sizes. The most common is the customary system where men's  shoes is one size shorter than the UK equivalent, making a men's 13 in the US the same size as a men's 12 in the UK. Customary. The customary system is offset by barleycorn, or , comparing to the UK sizes. The men's range starts at size 1, with zero point corresponding to the children's size 13 which equals barleycorns or . However most US manufacturers are using greater offsets, such as and 1 barleycorns. Therefore in current practice, US men's size 1 equals 25 barleycorns, or , so the calculation for a male shoe size in the  United States is: equivalent to: In the "standard" or "FIA" (Footwear Industries of America) scale, women's sizes are men's sizes plus 1 (so a men's is a women's ): equivalent to: There is also the "common" scale, where women's sizes are equal to men's sizes plus . Children's shoes start from size zero, which is equivalent to inches ( barleycorns = 99.48 mm), and end at . Thus the formula for children's sizes in the US is equivalent to: Alternatively, a Mondopoint-based scale running from K4 to K13 and then 1 to 7 is in  use. K4 to K9 are toddler sizes, K10 to K13 are pre-school and 1 to 7 are grade school sizes. Brannock Device. Brannock Device is a measuring instrument invented by Charles F. Brannock in 1925 and now found in many shoe stores. The recent formula used by the Brannock device assumes a foot length of 2 barleycorns less than the length of the last; thus, men's size 1 is equivalent to a last's length of and foot's length of , and children's size 1 is equivalent to last's length and foot's length. The device  also measures the length of the arch, or the distance between the heel and the ball (metatarsal head) of the foot. For this measurement, the device has a shorter scale at the instep of the foot with an indicator that slides into position. If this scale indicates a larger size, it is taken in place of the foot's length to ensure proper fitting. For children's sizes, additional wiggle room is added to allow for growth. The device also measures the width of the foot and assigns it designations of AAA, AA, A, B, C, D, E, EE, or  EEE. The widths are 3/16 inches apart and differ by shoe length. Some shoe stores and medical professionals use optical 3D surface scanners to precisely measure the length and width of both feet and recommend the appropriate shoe model and size. Continental Europe. In the Continental European system, the shoe size is the length of the last, expressed in Paris points or , for both sexes and for adults and children alike. Note that the last is typically longer than the foot heel to toe length by to , or 2 to Paris points, so to determine the shoe size based on  actual foot length one must add 2 Paris points. Because a Paris point is of a centimetre, the formula is as follows: equivalent to: The Continental European system is used in Austria, Belgium, Denmark, France, Germany, Italy, Luxembourg, the Netherlands, Norway, Poland, Portugal, Spain, Sweden, Switzerland, and most other continental European countries. It is also used in Middle Eastern countries (such as Iran), Brazil—which uses the same method but subtracts 2 from the final result, in effect measuring foot size instead of last size—and, commonly, Hong Kong. The system is sometimes described as Stich size (from "Pariser Stich , the German name for the Paris point), or Stichmaß" size (from a Geman name of a micrometer for internal measurements). Mondopoint. The Mondopoint shoe length system is widely used in sports industry to size athletic shoes, ski boots, skates, and pointe ballet shoes; it was also adopted as the primary shoe sizing system in the Soviet Union, Russia, East Germany, China, Japan, Taiwan, and South Korea, and as an optional system in United Kingdom, India, Mexico, and European countries. The Mondopoint system is also used by NATO and other military services. The Mondopoint system was introduced in the 1970s by  International Standard ISO 2816:1973 "Fundamental characteristics of a system of shoe sizing to be known as Mondopoint" and ISO 3355:1975 "Shoe sizes – System of length grading (for use in the Mondopoint system)". ISO 9407:2019, "Shoe sizes—Mondopoint system of sizing and marking", is the current version of the standard. The Mondopoint system is based on average foot length and foot width for which the shoe is suitable, measured in millimetres. The length of the foot is measured as horizontal distance between the perpendiculars in contact with the end of the most prominent toe and the most prominent part of the  heel. The width of the foot is measured as horizontal distance between vertical lines in contact with the first and fifth metatarsophalangeal joints. The perimeter of the foot is the length of foot circumference, measured with a flexible tape at the same points as foot width. The origin of the grade is zero. The labeling typically includes foot length, followed by an optional foot width: a shoe size of 280/110 indicates a foot length of and width of . Other customary markings, such as EU, UK and US sizes, may also be used. Because Mondopoint takes the foot width into account , it allows for better fitting than most other systems. A given shoe size shall fit every foot with indicated average measurements, and those differing by no more than a half-step of the corresponding interval grid. Standard foot lengths are defined with interval steps of 5 mm for casual footwear and steps of 7.5 mm for specialty (protective) footwear. The standard is maintained by ISO Technical Committee 137 "Footwear sizing designations and marking systems." East Asia. In Japan, mainland China, Taiwan, and South Korea, the Mondopoint system is used as defined by national standard Japanese Industrial Standards (JIS) S 5037:1998  and its counterparts Guobiao (GB/T) 3293.1-1998, Chinese National Standard (CNS) 4800-S1093:2000 and Korean Standards Association (KS) M 6681:2007. Foot length and girth (foot circumference) are taken into account. The foot length is indicated in centimetres; an increment of 5 mm is used. The length is followed by designators for girth (A, B, C, D, E, EE, EEE, EEEE, F, G), which are specified in an indexed table as foot circumference in millimetres for each given foot length; foot width is also included as supplemental information. There are different tables for men's, women's, and children's  (less than 12 years of age) shoes. Not all designators are used for all genders and in all countries. For example, the largest girth for women in Taiwan is EEEE, whereas in Japan, it is F. The foot length and width can also be indicated in millimetres, separated by a slash or a hyphen. Soviet Union (Russia, Commonwealth of Independent States). Historically the Soviet Union used the European (Paris point) system, but the Mondopoint metric system was introduced in the 1980s by GOST 24382-80 "Sizes of Sport Shoes" (based on ISO 2816:1973) and GOST 11373-88 "Shoe Sizes" (based  on ISO 3355:1975), and lately by GOST R 58149-2018 (based on ISO 9407:1991) Standard metric foot sizes can be converted to the nearest Paris point ( cm) sizes using approximate conversion tables; shoes are marked with both foot length in millimetres, as for pointe ballet shoe sizes, and last length in European Paris point sizes (although such converted "Stichmaß" sizes may come to 1 size smaller than comparable European-made adult footwear, and up to sizes smaller for children's footwear, according to ISO 19407 shoe size definitions). Foot lengths are aligned to 5 mm intervals for sports and casual  shoes, and 7.5 mm for protective/safety shoes. Optional foot width designations includes narrow, normal (medium or regular), and wide grades. Infant sizes start at 16 (95 mm) and pre-school kids at 23 (140 mm); schoolchildren sizes span 32 (202.5 mm) to 40 (255 mm) for girls and 32 to 44 (285 mm) for boys. Adult sizes span 33 (210 mm) to 44 for women and 38 (245 mm) to 48 (310 mm) for men. ISO 19407 and shoe size conversion. ISO/TS 19407:2015 "Footwear - Sizing - Conversion of sizing systems" is a technical specification from International Standards Organisation. It  contains basic description and conversion tables for major shoe sizing systems including Mondopoint with length steps of 5 mm and 7.5 mm, European Paris point system, and UK -inch system. The standard has also been adopted as Russian GOST R 57425-2017. The standard is maintained by ISO/TC 137, which also developed ISO/TS 19408:2015 "Footwear - Sizing - Vocabulary and terminology"; currently in development are companion standards ISO/TS 19409 "Footwear - Sizing - Measurement of last dimensions" and ISO/TS 19410 "Footwear - Sizing - Inshoe measurement". Shoe sizing. The adult shoe sizes are calculated from typical last length, which is converted from  foot length in mm by adding an allowance of two shoe sizes: formula_1 where "L" is foot length in mm. Direct conversion between adult UK, Continental European and Mondopoint shoe size systems is derived as follows: formula_2 Using these formulas, the standard derives shoe size tables for adults and children, based on actual foot length measurement (insole) in millimetres. Typical last length ranges are also included (13 to 25 mm over foot length for adults, 8% greater than foot length plus 6 mm for children). Exact foot lengths may contain repeating decimals because the formulas include division by 3; in  practice, approximate interval steps of 6.67 mm and 8.47 mm are used, and sizes are rounded to either size point or closest matching Mondopoint size. Size marking. It is recommended to mark include size marking in each of the four sizing systems on the shoe label and on the package. The principal system used for manufacturing the shoe needs to be placed first and emphasized with a boldface. The standard includes quick conversion tables for adult shoe size marking; they provide matching sizes for shoes marked in Mondopoint, European, and UK systems. Converted values are rounded to a larger shoe  size to increase comfort.