Shoe Size Calculator

Ordering footwear online often results in poor fit due to a lack of a unified global shoe standard. Sizing systems vary wildly by country, gender, and brand, making raw foot length measurements the only consistent point of reference for matching sizes across borders.

Our free online Shoe Size Conversion tool converts exact foot measurements and sizes across major global markets:

• Regional Sizing Support: US/Canada (men and women), UK/India, Europe (EU), Japan/Mexico, and China (CN).
• Metric & Imperial Inputs: Calculate matching sizes based on foot length in inches, centimeters, or millimeters.

Shoe Size Calculation Formulas

While minor differences exist between specific brand manufacturers, standard regional sizes can be calculated using strict mathematical formulas. The table below outlines how regional systems convert raw foot length (L) into a shoe size.

*Note: In the US, UK, and JP/MX systems, sizes increase in half-point increments. In the EU and China systems, sizes increase in whole-point increments.

International Shoe Sizing Reference Charts

The charts below provide standard conversions based on foot length. Compare regional sizes to identify the best starting point for a brand:

Women’s Shoes

Men’s Shoes

Standard Foot Sizing and Measurement Systems

Professional shoe fitting relies on specific physical devices to determine accurate foot proportions:

• The Brannock Device: The standard metal slider used by shoe fitters. It measures three distinct indicators:
  1. Foot length (heel to longest toe).
  2. Foot width (across the ball of the foot).
  3. Arch length (heel to the inside of the ball of the foot).
• The RITZ Stick: A wooden slide rule used historically before the Brannock device. It features simple length measurements alongside width conversion guides on the reverse side.
• The Mondopoint System: Sizing standard used primarily in high-performance sports (such as ski boots, ice skates, and ballet shoes), as well as general footwear in China, Japan, Taiwan, and South Korea. Based on exact measurements in millimeters, Mondopoint matches shoes to average foot length, width, and perimeter (the total circumference around the first and fifth metatarsophalangeal joints).

Key Factors that Influence Shoe Fit

Foot length is a helpful starting point, but a perfect fit depends on several structural factors:

• Foot Width and Shape: Individuals with wide metatarsal areas or high arches require wider fits (e.g., EEE, D, or AA widths) to prevent pinching. Regional sizing systems do not have a universal standard for width designations.
• Gender Differences: A woman’s foot is not simply a scaled-down version of a man’s. Women generally have different proportions, particularly around the arch, the ball of the foot, the first toe, and the heel, meaning gender-specific shoe shapes are essential.
• Age and Physical Changes: Ligaments and tendons stretch over time, causing feet to gradually lengthen and widen as we age.
• Brand Variations: Different manufacturers construct shoes using distinct physical molds, called “lasts.” Because of this, you may wear a size 9 in Nike and a size 9.5 in Adidas.

How to Measure Your Feet at Home

To measure your feet accurately:

1. Measure your feet later in the day, as standing causes feet to naturally swell.
2. Always fit shoes to your largest foot (most people have one foot that is slightly larger).
3. Choose slightly loose fits over tight fits for daily wear, leaving room to accommodate swelling. For specialized sports like soccer or rock climbing, a tighter fit can improve performance and dexterity at the cost of temporary comfort.

To check other clothing fit indicators, visit our Bra Size Calculator. For standard physical indexes, use the BMI Calculator.

Frequently Asked Questions (FAQ)

What is Mondopoint shoe sizing?

Mondopoint is an international shoe sizing system (measured in millimeters) that bases sizes on exact foot length and width. It is commonly used for specialized athletic gear like ski boots and skates, and serves as the standard sizing format in East Asia.

How do I convert European (EU) shoe sizes to US sizes?

For women, EU sizes are roughly 30 units higher than US sizes (e.g., a US 7 is a European 37 or 38). For men, EU sizes are typically 33 units higher than US sizes (e.g., a US 9 is a European 42). Use our converter tool to check specific mathematical differences.

Are US and UK shoe sizes the same?

No. UK sizes are generally one size smaller than US men’s sizes (e.g., a US men’s 9 is a UK 8) and two sizes smaller than US women’s sizes (e.g., a US women’s 7 is a UK 5).

Why do my feet seem larger than they were years ago?

As you age, the tendons and ligaments in your feet lose elasticity, causing the arch to flatten slightly. This natural flattening lengthens and broadens the foot, often requiring you to go up a half or whole shoe size.