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International Shoe Size Converter

Convert men's and women's footwear sizes between United States (US), United Kingdom (UK), and European (EU) standards.

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Select the gender-specific sizing type, enter your current size, and choose the target region to calculate the corresponding footwear fit.
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A Guide to International Footwear Sizing Systems

Shopping for shoes globally can be challenging due to the lack of a single, worldwide standardized shoe sizing system. Brands in different countries use distinct measurement units and sizing scales to describe the exact same physical length. Understanding the history of these standards and how to convert between US, UK, and European sizing can save you from returns and poor-fitting footwear.

Different Sizing Standards

The three primary regional sizing systems rely on historical units of measurement:

  • US Sizing: Based on the foot length in inches. The scale starts at size 1 for a 3.94-inch foot and increases by one-third of an inch (known historically as a barleycorn) per full size.
  • UK Sizing: Similar to the US system, but the scale starts slightly lower. A UK shoe size is generally one full size smaller than the US men's equivalent.
  • European (EU) Sizing: Based on a unit called the Paris Point, which is equal to two-thirds of a centimeter (6.67 mm). It is a unisex system that does not differentiate between men's and women's size numbers.

For general physical dimension changes, you can use our translating measuring units tool. For checking basic offsets, use our everyday daily math helper.

Conversion Math and Gender Offsets

Converting sizes is not a simple linear equation because of gender offsets in the US system. While a US men's size is one size larger than a UK size, a US women's size is typically 1.5 to 2 sizes larger than a UK size.

For example: - A UK men's size 9 is a US men's size 10. - A UK women's size 6 is a US women's size 8. - In Europe, both would translate to roughly an EU size 43 or 39 respectively.

To handle conversions that result in fractional sizes, you can check our decimal rounding utility.

Why Fits Can Vary

Although conversion formulas provide a close estimate, shoe shape (the last), width variations (medium, wide, narrow), and manufacturing tolerances mean that a converted size might not fit perfectly in every brand. Some manufacturers run large or small.

It is also helpful to measure your feet at the end of the day. Feet tend to expand due to gravity and daily walking, meaning a measurement taken in the evening will ensure you purchase footwear that remains comfortable throughout a full day of wear.

Additionally, you can calculate the average size of shoes in a group using our group average finder or compare dimensions using our relative ratio solver.

Always try to measure your foot length in centimeters or inches, as this represents a concrete physical size that bypasses regional labeling differences entirely.

Example Conversions

US Men's to European: Suppose a traveler wears a US Men's size 9. To convert to EU sizing, the general formula adds 33 to the US size: 9 + 33 = 42 (approximately EU 42 or 42.5).

US Women's to UK: Suppose a customer wears a US Women's size 8.5. To convert to UK sizing, subtract 2 full sizes: 8.5 - 2 = 6.5. The equivalent UK size is 6.5.

EU to US Men's: An EU size 45 translates to a US Men's size 11.5. These examples show how to easily navigate online footwear size tables.