Methodology

How we collect and verify sizing data

Sources

• ISO 9407 (shoe sizing / Mondopoint) and ISO 8559 (garment measurement).
• EN 13402 for European clothing size labeling.
• Official brand measurement and fit guidance, linked in source-backed journal articles.
• Approximate international reference tables; these are not product-specific measurements.

Reconciliation

There is no universal US-to-EU chart that guarantees fit across brands. Standards describe measurement and labeling systems; manufacturers choose their own lasts and conversions. Use our general tables as a starting point and the current product chart for the final decision. A CM/JP label is not necessarily the measured foot length, as Nike explicitly notes in its footwear charts.

Rounding

Different sizing increments do not align exactly. Tables display approximate equivalents, and calculators have a limited supported range. Between-size decisions depend on the manufacturer and intended fit; automatically rounding down is not a safe rule.

Fit notes

Fit depends on the model, version, width, material and wearer. General brand descriptions are not controlled wear-test results. Do not apply a half-size adjustment across an entire brand; check the product’s own guidance and try the footwear with the intended socks.

Limitations

Sizing charts describe average feet and average bodies. They cannot account for individual foot volume, arch height, or personal preference for looseness. Always confirm fit with the retailer's own chart before purchase.