With the UK Shoe Size Converter, you can convert any British UK shoe size into other common shoe size systems, such as the Mondopoint system. Conversely, you can also convert your EU size into the appropriate UK shoe size. You can choose whether you want to calculate the UK shoe size for men and women or the UK shoe size for children.
Calculation examples of UK Sizes
Information on British shoe sizes (the UK sizes)
From a foot length of 10.16 cm, 13 children's shoe sizes of 0.847 cm each are defined—after which the sizes for women and men start again with Size 1. The basis is usually the length of the foot, as well as the interior length or the length of the shoe last in accordance with the ISO standard. This is one of the reasons why shoe sizes vary greatly.
Calculation of UK shoe sizes according to ISO/TS 19407:2015
The UK Shoe Size Calculator calculates sizes according to ISO. Likewise, the UK shoe size tables presented a map to the same ISO specification. The ISO (International Organization for Standardization) has defined the conversion of shoe size systems and thus issued this international pre-standard.
Nevertheless, there are very frequent deviations from the English shoe sizes theoretically calculated here. Therefore, shoes often turn out smaller or larger depending on the manufacturer or simply due to deviating standardisations.
ISO formula for calculating the UK shoe size for adults
UK shoe size
(foot length + 2 × 0.847) / 0.847 − 25
The formula for UK adult size makes it clearer that each size corresponds to 0.847 cm. For toe clearance, as is usually the case, two sizes are added (i.e., 2 × 0.847 cm). Finally, 25 sizes are subtracted in the formula. These are the “empty” 12 sizes at the beginning and the 13 children's sizes that follow.
ISO formula for calculating the UK shoe size for children
UK children shoe size
Foot length × 1.08 / 0.847 − 12 + 0.4
Compared to the adult formula, a surcharge of 8 percent of the foot length is added for toe clearance, instead of the two English sizes. Here, only the 12 "empty" (i.e., the unoccupied sizes) are deducted at the beginning. Finally, for the ISO formula, 0.4 sizes are added again to obtain practical size tables.
Shoe size chart for UK shoe sizes for men and women
According to the official ISO technical specification, the following shoe size table is for all British shoe sizes. Unlike the US system, UK shoe sizes (just like EU sizes) make no distinction between UK women's shoe sizes and UK men's shoe sizes.
|UK adult shoe size chart according to ISO specification ISO/TS 19407:2015|
|UK||Mondopoint||EU||US men||US women|
|UK||Mondopoint||EU||US men||US women|
UK size chart for adults to print
UK Shoe Sizes Chart for Children
In the UK and the USA, different numbers are assigned to children's shoe sizes than to adult shoe sizes. After a total of 13 UK children's shoe sizes, the UK shoe sizes for adults follow, starting with Shoe Size 1. Based on the ISO specification, the following shoe size chart is recommended for all UK children's shoe sizes.
|UK shoe size chart for children according to ISO specification ISO/TS 19407:2015|
|UK||foot length, inch||foot length, cm||Mondopoint||EU||US|
|UK||foot length, inch||Foot length, cm||Mondopoint||EU||US|
This size chart for UK shoes according to ISO leaves some fields open. This is because the official ISO formula has not determine a counterpart in other respective size units at the corresponding position. However, the UK Shoe Size Converter also determines the rounded sizes for the missing fields. The calculation and rounding are explained behind the “info” buttons in the result.
Printable UK size chart for children
What are EU Sizes 38 or 43 in UK or US sizes?
If you want to know which shoe sizes correspond to, for example, EU Shoe Size 38, 42 or 43, you can either use the Shoe Size Converter, or the matching shoe size chart, or check your US or UK shoe size on the following pages:
What is EU Shoe Size 20?, What is EU Shoe Size 21?, What is EU Shoe Size 22?, What is EU Shoe Size 23?, What is EU Shoe Size 24?, What is EU Shoe Size 25?, What is EU Shoe Size 26?, What is EU Shoe Size 27?, What is EU Shoe Size 28?, What is EU Shoe Size 29?, What is EU Shoe Size 30?, What is EU Shoe Size 31?, What is EU Shoe Size 32?, What is EU Shoe Size 33?, What is EU Shoe Size 34?, What is EU Shoe Size 35?, What is EU Shoe Size 36?, What is EU Shoe Size 37?, What is EU Shoe Size 38?, What is EU Shoe Size 39?, What is EU Shoe Size 40?, What is EU Shoe Size 41?, What is EU Shoe Size 42?, What is EU Shoe Size 43?, What is EU Shoe Size 44?, What is EU Shoe Size 45?, What is EU Shoe Size 46?, What is EU Shoe Size 47?, What is EU Shoe Size 48?, What is EU Shoe Size 49?, What is EU Shoe Size 50?.
An example for the conversion of the UK shoe size
Mrs Shoemaker wants to buy new shoes. She has a UK Shoe Size 7. In the Shoe Size Converter, she input her UK shoe size to calculate the sizes of the other shoe size systems.
1. Calculation of the foot length based on the UK size
First, Mrs Shoemaker's foot length is calculated using the UK Shoe Size 7. The foot length then serves as the basis for calculating the EU size (i.e., the former "German", "Italian" or "French" shoe size). For this purpose, the ISO formula for calculating the UK shoe size is converted accordingly on the basis of the foot length.
ISO formula for calculating the UK size
UK shoe size = (foot length + 2 × 0.847) / 0.847 − 25
- One UK size is equal to one-third of an inch (0.847 cm).
- The first 12 UK sizes are not numbered.
- The following 13 sizes are allocated as children's sizes
- The English shoe sizes for adults start with Size 1 after the children's sizes.
- Therefore, 25 sizes are deducted in total
- In addition, two UK shoe sizes toe clearance (i.e., 2 × 0.847 cm) will be added on.
Converted UK formula for calculating foot length
Foot length in cm = (UK size + 25) × 0.847 − 2 × 0.847
Calculation of Mrs Shoemaker's foot length
(7 + 25) × 0.847 − 2 × 0.847 = 25.41 cm
With the help of this foot length, Mrs Shoemaker’s UK shoe size is converted to other shoe size systems as shown below (i.e., for EU sizes, US sizes and Mondopoint sizes) using the respective ISO formula.
2. Calculate the EU size according to Mrs Shoemaker’s foot length
To determine Mrs Shoemaker's EU size, the appropriate ISO conversion formula is first used based on her foot length. Then the result of this calculation is rounded to the nearest whole or half size.
Formula for EU size
EU shoe size = (foot length in cm + 2 × 0.667) / 0.667
- One size equals two-thirds of a centimetre, i.e., 0.667 cm
- Sizes start at 0
- Two sizes of toe clearance are added on, i.e., 2 × 0.667 cm.
Here, you can find more comprehensive information on EU shoe sizes .
Calculation of the EU size
(25.41 cm + 2 × 0.667) / 0.667 = 40.096 EU
Rounding the result
Rounded to the nearest whole or half size, this results in Size 40.0 EU for Mrs Shoemaker.
Mrs Shoemaker’s UK Shoe Size 7 corresponds to EU Size 40 after conversion.
3. Calculate the US shoe size using Mrs Shoemaker's foot length
To determine Mrs Shoemaker’s US size, the appropriate ISO conversion formula for US sizes is used based on her foot length. Then the result of the calculation is also rounded to the nearest whole or half size.
At this point, it can be revealed that Mrs Shoemaker's US shoe size is 9.0. According to the ISO standard, US women's shoe sizes are always two sizes larger than the UK shoe size (i.e., in Mrs Shoemaker's case, two sizes are larger than her UK Size 7). In this respect, it is not surprising that the application of the ISO formula ultimately leads to this result, as shown below.
ISO formula for US size
US women size = (foot length + 2 × 0.847) / 0.847 − 23
- According to the UK system, one size corresponds to one-third of an inch, i.e., 0.847 cm
- The first 12 sizes are not numbered.
- The following 13 shoe sizes are reserved for children's sizes
- Women's sizes start with Size 0 after these children's sizes.
- Therefore, 23 sizes are subtracted because, in practice, the US system is largely aligned with the UK system. However, US women's sizes are two sizes larger than the corresponding UK shoe sizes for the same foot length.
- Two sizes of toe room are added, i.e., 2 × 0.847 cm.
Here, you can find more comprehensive information on US shoe sizes .
Calculation of the US size
(25.41 cm + 2 × 0.847) / 0.847 − 23 = 9.0 US
Rounding the result
Rounded to the nearest whole or half size, this still gives Mrs Shoemaker Size 9.0 US Ladies.
Mrs Shoemaker’s UK Shoe Size 7 corresponds to US women's Size 9 after conversion.
4. Calculate Mondopoint shoe size to Mrs Shoemaker's foot length.
Converting the foot length to the Mondopoint system is rather easy because Mondopoint sizes indicate the foot length in millimetre.
ISO formula for Mondopoint size
Mondopoint size = foot length (cm) × 10
Here, you can find more comprehensive information on Mondopoint shoe sizes .
Calculation of the Mondopoint size
25.41 cm × 10 = 254.1 Mondopoint
Rounding the result
Rounded to the nearest Mondopoint size, this gives Mrs Shoemaker Size 255 Mondopoint.
Mrs Shoemaker's UK Shoe Size 7 is the same as Mondopoint Size 255. after conversion.
What other readers have also read
More online calculators
Length Converter, Percent Calculator, Convert Temperatures, Converting Units of Weight, Calculating Pregnancy Week, Calculator
As source for the information in the 'Sizes of Shoe' category, we have used in particular:
- ISO specification ISO/TS 19407:2015(E) "Footwear-Sizing-Conversion of sizing systems" from International Organization for Standardization
- Show size (Wikipedia)
Last update on February 19, 2023
The pages of the 'Sizes of Shoe' category were last editorially reviewed by Stefan Banse on February 19, 2023. They all correspond to the current status.
Previous changes on May 10, 2021
- May 10, 2021: Articles about Nike shoe sizes and adidas shoe sizes
- May 01, 2021: Publication of the Shoe size converter
- Editorial revision of all texts in this category