Shoe Size Converter

This page converts a size you already have. Type a US, UK, EU or centimetre figure into any field and the rest follow. If instead you have a tape measure and a purchase to make, the shoe size from foot length page starts from the measurement and adjusts the answer for dress shoes, running shoes or boots over thick socks. Both pages run the same conversion model, so they agree on the numbers.

Shoe size conversions are based on foot length in centimeters.

Conversion formulas (approximate):

• US Men to cm: cm = 24.0 + (US_Men - 6) × 1.0
• US Women = US Men + 1.5
• UK Men = US Men - 0.5
• EU = cm × 1.5 + 2

Reference table:

Note: Shoe sizes vary between manufacturers. These conversions are approximate guidelines.

Two different step sizes, and why the table uses the rounder one

The English size system, which the US inherited, is built on the barleycorn: one full size is 1/3 of an inch, so a half size is 1/6 of an inch, about 4.2 mm. That is the definition. What manufacturers actually print on their own centimetre charts is a flat 0.5 cm per half size, which is the step used in the table above. The two disagree by roughly a fifth of a step, and after four or five sizes that adds up to a few millimetres.

Neither one is wrong; they answer different questions. The barleycorn is what the size scale is made of. The 0.5 cm step is what Nike, Asics and everyone else publish next to their size numbers, so it is the one that matches the box you will actually buy.

Where the EU “+2” comes from

The European scale counts Paris points, and one Paris point is 2/3 of a centimetre. It measures the last, the form the shoe is built around, not your foot, and a last runs about 1.3 cm longer than the foot inside it. Multiply that out and you get EU = (foot cm + 1.33) x 1.5, which is exactly the cm x 1.5 + 2 in the formula list. So the odd-looking +2 is the toe room, converted into Paris points.

The only system that measures the actual foot is Mondopoint, the centimetre length used on ski boots and by the military. Every other scale is an indirect code.

The practical takeaway is to trust foot length over any size number. Stand on a sheet of paper with your heel against a wall, mark the longest toe, measure both feet and use the bigger one, and do it late in the day when feet are at their largest. Then work from that number, because a “size 10” varies not only between countries but between brands and between two styles from the same brand. A chart gets you close; trying them on is what confirms it.