Shoe size 250: what is that number measuring?

Korea writes the length of the foot directly in millimeters. Sizes usually step up in 5 mm intervals, so after 245 comes 250, and then 255. The advantage is that the number alone tells you how many centimeters long your foot is.

A common misunderstanding is that the inside of a size 250 shoe is exactly 250 mm long. In fact, the inside of a shoe is made a little longer than the foot so the toes have room to move. How much room is left differs by brand and by shoe shape, so even at the same 250, one pair may feel roomy while another feels tight.

US sizes are based on inches. Each size is one third of an inch, about 8.5 mm, larger than the last, and the story goes that this step comes from old England, where three grains of barley were counted as one inch. On top of that, men's and women's sizes start from different points, so the same number 8 means different shoe lengths for men and women.

With European sizes such as 40 or 42, each size is two thirds of a centimeter, about 6.7 mm. This system measures the length of the form used to make the shoe rather than the foot, so converting the number to centimeters gives a length longer than the actual foot. A 40 works out to about 26.7 cm, yet it is usually worn by people whose feet are around 25 cm long.

Conversion charts between countries are only approximate. Because each system measures a different thing at different intervals, they never line up exactly, so when buying from an overseas store, the foot-length chart that the brand itself posts is more accurate.

To measure at home, stand on a sheet of paper with your heel against a wall and mark the tip of your longest toe. Feet swell a little as the day goes on, so measuring toward evening is best, and since many people have feet of slightly different lengths, go by the longer one. If you have wide feet, check the width as well, not just the length.