British and Americans still use inches instead of metric centimetres to measure length. Therefore, shoe sizes are also assigned on the basis of inches. It is not only for babies that shoe sizes are determined (based on foot length in inches), but children's and adults' shoe sizes can also be converted to all international shoe sizes (based on foot length in inches) using the Shoe Size Converter. In the Shoe Size Converter, simply select "Foot length in inches". The calculator converts the inches into centimetres (1 inch = 2.54 cm) and then it also converts the foot length into the sizes of other shoe size systems using the international ISO formula based on centimetres.
Shoe size in inches - examples
Calculation of shoe sizes in inches according to ISO/TS 19407:2015
The foot length in inches is first converted into centimetres and then into the shoe size of other respective size systems according to ISO formulas, i.e., the EU-, UK-, US- or Mondopoint-System. The following shoe size tables for foot length in inches are also based on this ISO specification. The ISO (the International Organization for Standardization) has defined the conversion of shoe size systems and thus issued this international pre-standard. However, there are often deviations from the theoretically calculated shoe sizes in inches. Therefore, shoes often turn out smaller or larger simply because of deviating standardisation or depending on the manufacturer.
Basic information on converting shoe sizes to inches
All ISO conversion formulas refer to foot length. In the case of non-ISO size specifications, the length of the last in inches or the interior length of the shoe in inches is sometimes also chosen as the reference for calculating shoe sizes. On the other hand, for international standardisation, the foot length in centimetres or inches is the means of choice.
Normally, the foot length is used in the ISO formula to calculate the respective shoe size. If you want to determine the foot length based on shoe size, the corresponding ISO formula is converted so that the result of the formula is the foot length (e.g., in inches), instead of the shoe size. This conversion formula is explained in detail in the examples below.
Measure foot length in inches
To accurately measure the foot length, it is best to place a sheet of paper against a wall and place the foot on it so that the heel is directly against the wall and thus against the edge of the paper. Now draw along the toes with a pencil. It is important to hold the pencil straight at a 90° angle. Then measure the length from the back edge of the paper to the longest toe. Ensure you measure both feet, as they can often be of different lengths. Since the feet only reach their full size during the day, it is better to measure in the afternoon.
Shoe size chart to convert foot length to inches for adults
Based on the ISO technical specification, the following shoe size table is given for different foot lengths in inches. According to the conversion from inches to centimetres (1 inch = 2.54 cm), the foot lengths are also given in centimetres. Each foot length in inches is thus assigned the appropriate shoe sizes of the individual shoe size systems.
| Foot length in inches to adult shoe size chart according to ISO specification ISO/TS 19407:2015 | ||||||
|---|---|---|---|---|---|---|
| Foot length (inches) | Foot length (cm) | Mondopoint | EU | UK | US men | US women |
| 8.4 | 21.3 | 215 | 34 | 2 | 3 | 4 |
| 8.5 | 21.7 | 215 | 34.5 | 2.5 | 3.5 | 4.5 |
| 8.7 | 22.0 | 220 | 35 | 3 | 4 | 5 |
| 8.8 | 22.3 | 225 | 35.5 | 3.5 | 4.5 | 5.5 |
| 8.9 | 22.7 | 225 | 36 | 4 | 5 | 6 |
| 9.1 | 23.0 | 230 | 36.5 | 4 | 5 | 6 |
| 9.2 | 23.4 | 235 | 37 | 4.5 | 5.5 | 6.5 |
| 9.3 | 23.7 | 235 | 37.5 | 5 | 6 | 7 |
| 9.4 | 24.0 | 240 | 38 | 5.5 | 6.5 | 7.5 |
| 9.6 | 24.4 | 245 | 38.5 | 5.5 | 6.5 | 7.5 |
| 9.7 | 24.7 | 245 | 39 | 6 | 7 | 8 |
| 9.8 | 25.0 | 250 | 39.5 | 6.5 | 7.5 | 8.5 |
| 10.0 | 25.4 | 255 | 40 | 7 | 8 | 9 |
| 10.1 | 25.7 | 255 | 40.5 | 7.5 | 8.5 | 9.5 |
| 10.2 | 26.0 | 260 | 41 | 7.5 | 8.5 | 9.5 |
| 10.4 | 26.4 | 265 | 41.5 | 8 | 9 | 10 |
| 10.5 | 26.7 | 265 | 42 | 8.5 | 9.5 | 10.5 |
| 10.6 | 27.0 | 270 | 42.5 | 9 | 10 | 11 |
| 10.8 | 27.4 | 275 | 43 | 9.5 | 10.5 | 11.5 |
| 10.9 | 27.7 | 275 | 43.5 | 9.5 | 10.5 | 11.5 |
| 11.0 | 28.0 | 280 | 44 | 10 | 11 | 12 |
| 11.2 | 28.4 | 285 | 44.5 | 10.5 | 11.5 | 12.5 |
| 11.3 | 28.7 | 285 | 45 | 11 | 12 | 13 |
| 11.4 | 29.0 | 290 | 45.5 | 11.5 | 12.5 | 13.5 |
| 11.6 | 29.4 | 295 | 46 | 11.5 | 12.5 | 13.5 |
| 11.7 | 29.7 | 295 | 46.5 | 12 | 13 | 14 |
| 11.8 | 30.0 | 300 | 47 | 12.5 | 13.5 | 14.5 |
| 12.0 | 30.5 | 305 | 47.5 | 13 | 14 | 15 |
| 12.1 | 30.7 | 305 | 48 | 13 | 14 | 15 |
| 12.2 | 31.0 | 310 | 48.5 | 13.5 | 14.5 | 15.5 |
| 12.4 | 31.4 | 315 | 49 | 14 | 15 | 16 |
| 12.5 | 31.7 | 315 | 49.5 | 14.5 | 15.5 | 16.5 |
| 12.6 | 32.00 | 320 | 50 | 15 | 16 | 17 |
| Foot length (inches) | Foot length (cm) | Mondopoint | EU | UK | US men | US women |
Printable inch size chart for adults
Shoe size chart to convert foot length to inches for children
In the conversion formulae for children, the toe clearance is calculated slightly differently from that of adults. For children, instead of an allowance of two shoe sizes, an allowance of eight percent of the foot length in inches is used. Also, in both the UK and US systems, children's sizes are numbered differently from adult sizes. In the UK and US, 13 children's sizes are followed by adult sizes starting with 0 or 1. Based on the ISO specification, the following shoe size chart is recommended for all children's shoe sizes.
| Foot length in inches to shoe size chart for children according to ISO specification ISO/TS 19407:2015 | |||||
|---|---|---|---|---|---|
| Foot length (inches) | Foot length (cm) | Mondopoint | EU | UK | US |
| 4.7 | 12.0 | 120 | 19.5 | 3.5 | 4 |
| 4.8 | 12.3 | 125 | 20 | 4 | 4.5 |
| 5.0 | 12.7 | 20.5 | 4.5 | 5 | |
| 5.1 | 13.0 | 130 | 21 | 5 | 5.5 |
| 5.2 | 13.3 | 21.5 | 5.5 | 6 | |
| 5.3 | 13.5 | 135 | 22 | ||
| 5.4 | 13.8 | 140 | 22.5 | 6 | 6.5 |
| 5.6 | 14.2 | 23 | 6.5 | 7 | |
| 5.7 | 14.6 | 145 | 23.5 | 7 | 7.5 |
| 5.8 | 14.8 | 24 | |||
| 5.9 | 15.0 | 150 | 24.5 | 7.5 | 8 |
| 6.1 | 15.4 | 155 | 25 | 8 | 8.5 |
| 6.2 | 15.7 | 25.5 | 8.5 | 9 | |
| 6.3 | 16.0 | 160 | 26 | 9 | 9.5 |
| 6.5 | 16.4 | 26.5 | |||
| 6.5 | 16.6 | 165 | 27 | 9.5 | 10 |
| 6.7 | 16.9 | 170 | 27.5 | 10 | 10.5 |
| 6.8 | 17.3 | 28 | 10.5 | 11 | |
| 6.9 | 17.6 | 175 | 28.5 | 11 | 11.5 |
| 7.0 | 17.9 | 180 | 29 | 11.5 | 12 |
| 7.2 | 18.2 | 29.5 | |||
| 7.3 | 18.5 | 185 | 30 | 12 | 12.5 |
| 7.4 | 18.8 | 30.5 | 12.5 | 13 | |
| 7.6 | 19.2 | 190 | 31 | 13 | 13.5 |
| 7.7 | 19.5 | 195 | 31.5 | 13.5 | 1 |
| 7.8 | 19.8 | 32 | |||
| 7.9 | 20.0 | 200 | 32.5 | 1 | 1.5 |
| 8.0 | 20.4 | 205 | 33 | 1.5 | 2 |
| 8.1 | 20.7 | 33.5 | |||
| 8.3 | 21.0 | 210 | 34 | 2 | 2.5 |
| 8.4 | 21.3 | 34.5 | 2.5 | 3 | |
| 8.5 | 21.7 | 215 | 35 | 3 | 3.5 |
| 8.7 | 22.0 | 220 | 35.5 | 3.5 | 4 |
| 8.8 | 22.4 | 36 | |||
| 8.9 | 22.6 | 225 | 36.5 | 4 | 4.5 |
| 9.1 | 23.0 | 230 | 37 | 4.5 | 5 |
| 9.1 | 23.2 | 37.5 | |||
| 9.3 | 23.6 | 235 | 38 | 5 | |
| Foot length (inches) | Foot length (cm) | Mondopoint | EU | UK | US |
Some fields are not filled in this ISO size table for converting foot lengths in inches to shoe sizes. This is because the official ISO formula is yet to determine the exact value in the other respective size units at the corresponding position. However, the Shoe Size Converter for foot length in inches also determines the corresponding rounded sizes for the fields that are still open. Both the calculation and the rounding are then explained in detail in the calculator result at the "info" buttons.
Printable inch size chart for children
Example 1: Calculating foot length in inches using US size
Ms Klein has a US Shoe Size 7.5 and would like to use this size to calculate her foot length in inches. To do this, the ISO formula for calculating the US shoe size for women is converted accordingly.
ISO formula for calculating US women's size
US women's shoe size = (foot length in cm + 2 × 0.847) / 0.847 − 23
Explanation
- One US size is equal to one-third of an inch (0.847 cm).
- The first 11 US sizes are not numbered.
- The following 13 sizes are assigned as children's sizes.
- The American shoe sizes for women start with Size 0 following the children's sizes.
- Therefore, 23 sizes in total are subtracted.
- In addition, two US shoe sizes toe clearance, i.e., 2 × 0.847 cm, are added on.
Modified formula for calculating the foot length
Foot length in cm = (US women's shoe size + 23) × 0.847 − 2 × 0.847
Calculation of Ms Klein's foot length
(7.5 + 23) × 0.847 − 2 × 0.847 = 24.14 cm
When converted into inches, Ms Klein has a foot length of 9.5 inches.
Using this foot length in inches, the shoe sizes for the other size systems can then be calculated using the respective ISO formula.
Example 2: Calculating EU size using foot length in inches
Ms Klein's US Shoe Size 7.5 corresponds to a foot length of 9.5 inches, as shown in Example 1. Now, based on her foot length, we will calculate her corresponding EU shoe size here. To determine Ms Klein's EU size, we will first use the appropriate ISO conversion formula based on her foot length. Then the calculation result 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
Explanation
- One size equals two-thirds of a centimetre, i.e., 0.667 cm (0.2625 inch).
- Sizes start at 0.
- Two sizes of toe clearance, i.e., 2 × 0.667 cm are added on.
Read more comprehensive information on EU shoe sizes here.
Calculation of the EU size
Ms Klein's foot length of 9.5 inches must first be converted into centimetres in order to use the ISO formula. Here, 9.5 inches corresponds to 24.13 centimetres. These can now be inserted into the formula.
(24.13 cm + 2 × 0.667) / 0.667 = 38.177 EU
Rounding the result
Rounded to the nearest whole or half size, this gives Ms Klein Shoe Size 38 EU.
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Source information
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