What is Shoe Sizing?
Shoe sizing is an alphanumeric indication of the fitting size of a shoe for a person. Unlike many other products, there is no single global standard. A size "10" in the US is very different from a size "10" in the UK.
Our AI-enhanced tool unifies these fragmented systems, calculating the corresponding Men's, Women's, and Kids' sizes based on the raw centimeter or inch length of the foot.
How to Measure Foot Length?
For the best results, use the "Paper Method":
Place a piece of paper on the floor against a wall. Stand on it with your heel firmly touching the wall.
Mark the tip of your longest toe on the paper with a pen.
Measure the distance from the edge of the paper (heel) to the mark (toe) in cm or inches.
Did you know most people have one foot slightly larger than the other? Our AI algorithm recommends measuring both feet and using the measurement from the larger foot to determine your size.
International Size Comparison
See how the numbering systems differ across regions for a typical adult measurement.
| Region | Men's Example | Women's Example | System Origin |
|---|---|---|---|
| US / Canada | 9 | 10.5 | Barleycorn unit |
| UK | 8 | 8.5 | Barleycorn unit |
| Europe (EU) | 42 | 42 | Paris Point (2/3 cm) |
| CM / JP | 27 | 27 | Centimeters (Direct) |
Frequently Asked Questions
Why are Men's and Women's US sizes different?
In the US system, there is typically a 1.5 size difference. A Men's size 7 is roughly a Women's size 8.5. Our calculator handles this gender conversion automatically.
What about width (Wide/Narrow)?
This calculator determines Length Size only. If you have wide feet, it is often recommended to go up a half size to accommodate the extra width comfortably.
Disclaimer
This AI Shoe Size Calculator provides estimates based on generic industry formulas. Shoe sizing varies significantly between brands (e.g., Nike vs. Adidas) and styles (Sneakers vs. Boots). Always refer to the specific brand's size chart before purchasing.