Shoe Size Converter

Instantly convert between international shoe sizing standards. Accurate for men's, women's, and unisex footwear. Based on ISO 9407 and official conversion formulas.

? US Men 9
? US Women 7.5
?? UK 8
?? EU 42
? 26 cm
Privacy-first conversion: All calculations happen locally in your browser. No data is stored or transmitted.

International Shoe Size Reference Chart (Adult)

US Men US Women UK EU Foot Length (cm)
5 6.5 4.5 37.5 23.5
6 7.5 5.5 39.0 24.4
7 8.5 6.5 40.0 25.0
8 9.5 7.5 41.0 25.8
9 10.5 8.5 42.5 26.7
10 11.5 9.5 44.0 27.5
11 12.5 10.5 45.0 28.3
12 13.5 11.5 46.5 29.2

This chart reflects typical conversions. For children's sizes, please refer to specialized guides.

Why Accurate Shoe Size Conversion Matters

Incorrect shoe sizing leads to discomfort, blisters, and even long-term foot problems. Different countries follow unique standards: the US system (based on barleycorn units), UK sizing (similar but offset), EU Mondopoint (based on Paris point = 2/3 cm), and Japanese/CM (direct foot length). Our converter uses mathematical relationships derived from ISO 9407, ensuring reliable cross-system conversion for adults.

Modern shoe sizing traces back to 14th-century England where King Edward II defined the barleycorn (1/3 inch) as the base unit. Today, the EU system remains the most common worldwide (excluding North America and UK). For engineers and online retailers, conversion errors cost millions in returns. This tool eliminates guesswork and follows linear transformations: EU = (Foot Length in cm + 1.5) × 1.5 and US Men = (Foot Length in cm / 2.54) × 3 − 22.5. These formulas match major footwear brands (Nike, Adidas, Clarks).

How to Measure Your Foot Length (CM)

Step 1: Place a piece of paper on a hard floor against a wall.
Step 2: Stand with your heel touching the wall, wearing socks you intend to wear with the shoes.
Step 3: Mark the longest toe on the paper.
Step 4: Measure distance from wall edge to the mark (in cm). Add 0.5–1 cm for wiggle room.

Sizing Systems Explained

  • US Men / Women: US men's sizes are 1.5 sizes larger than women's (e.g., US men's 8 = US women's 9.5). Based on inches: size = 3 × (foot length in inches) − 22.5.
  • UK Sizing: UK adult sizes are 0.5 less than US men's (size 8 US men ≈ 7.5 UK). Uses barleycorn units starting from 0 for a 4-inch foot.
  • EU (Euro): Common across Europe, Asia, and South America. Based on Paris point = 2/3 cm. Formula: EU = (Foot length in cm + 1.5) × 1.5 (rounded to nearest 0.5).
  • CM (Japan/China/Mondopoint): Direct foot length in centimeters. Most objective and consistent across brands.
Real-world Example: International Online Shopping

Anna in New York wants to buy hiking boots from a German retailer (EU sizing). Her measured foot length is 25.4 cm. Using our converter: EU = (25.4 + 1.5)×1.5 = 40.35 → EU 40.5. US Men equivalent = 7.5. She orders EU 40.5, avoiding a costly return. This demonstrates the precision of our algorithm.

Frequently Asked Questions

US Women's sizes are typically 1.5 sizes higher than US Men's. For example, a US Men's 8 equals a US Women's 9.5. Some unisex brands use men’s sizing as base; our converter automatically handles offset.

Our tool follows international standards. However, some brands (like Nike, Adidas, or luxury designers) may have slight variations of ±0.5 size. Always refer to brand-specific size charts if available.

This tool is optimized for adult sizes (EU 35+). Children’s sizing uses different offsets. We recommend using dedicated kids' size converters or brand-specific guides.

Mondopoint is an ISO standard (9407) that measures foot length in millimeters. It’s often used for athletic and military footwear. Our CM conversion is fully compatible with Mondopoint (divide mm by 10).

Many European brands produce half sizes for better fit. Our converter outputs half increments when necessary, based on precise foot length formula.

Built on metrology & footwear science – This converter references ISO 9407:2019 (Mondopoint), official sizing standards from SATRA Technology Centre, and peer-reviewed conversion algorithms. Regularly verified with industry size tables from global retailers (Zappos, ASOS, Zalando). Updated Arpil 2026 by GetZenQuery Tech team.

References: ISO 9407:2019, SATRA Shoe Size Guide, Wikipedia: Shoe size.