Shoe Size Conversion Calculator

• •Use the Shoe Size Conversion Calculator when you need accurate results quickly without the risk of manual computation errors or unit conversion mistakes.
• •Use it to verify calculations made by hand or in spreadsheets — an independent check can catch errors before they lead to costly decisions.
• •Use it to explore how changing input parameters affects the output — a quick way to develop intuition and identify the most influential variables.
• •Use it when collaborating with others to ensure everyone is working from the same numbers and applying the same assumptions.

Shoe sizing varies across countries and even between manufacturers, making international shopping confusing. The Shoe Size Conversion Calculator provides approximate conversions between US, UK, and EU sizing systems, along with the US men's-to-women's conversion. US and UK sizes use a numbered system where each size represents roughly one-third of an inch (8.46 mm) in foot length, while EU sizes use the Paris Point system where each size equals two-thirds of a centimeter (6.67 mm). These approximations work well for most brands but can vary by up to a full size between manufacturers, so always consult the specific brand's size chart when possible.

• !Assuming all brands use the same sizing; Nike tends to run small, New Balance runs true, etc.
• !Forgetting the men's-to-women's offset when shopping across gender categories.
• !Not measuring foot length directly; your size may have changed since you last measured.