Shoe Size Converter Formula

Understand the math behind the shoe size converter. Each variable explained with a worked example.

Use the Shoe Size Converter

Formulas Used

EU Size

eu_size = us_size + 31.5

UK Size

uk_size = us_size - 0.5

Foot Length (cm)

cm_size = us_size * 0.847 + 16.5

Variables

VariableDescriptionDefault
us_sizeUS Shoe Size(US)10

How It Works

Shoe Size Converter

Approximate Formulas (Men's Sizes)

  • EU Size ≈ US Size + 31.5
  • UK Size ≈ US Size - 0.5
  • Foot Length (cm) ≈ US Size × 0.847 + 16.5

    • Note: Shoe sizing varies between brands. These are approximate conversions.

    Worked Example

    Convert US men's size 10 to EU and UK sizes.

    us_size = 10
    1. 01EU Size = 10 + 31.5 = 41.5 EU
    2. 02UK Size = 10 - 0.5 = 9.5 UK
    3. 03Foot Length = 10 × 0.847 + 16.5 = 24.97 cm

    Frequently Asked Questions

    How do I convert US shoe size to EU?

    For men's shoes, add approximately 31.5 to the US size to get the EU size. For example, US 10 ≈ EU 41.5.

    Are shoe size conversions exact?

    No, shoe size conversions are approximate. Sizing varies between brands and styles. Always try shoes on when possible.

    Ready to run the numbers?

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