Ski boots are measured in Mondopoint sizing; ski boot charts will translate the Mondo or centimeter size into the United States size or translate the size into its U.S. equivalent by adding both digits of the Mondopoint size in centimeters. For example, if the metric size is 23, add 2 plus 3. The size is a U.S. men's size 5.
There are several ways to use a ski boot sizing chart. The easiest being to take the U.S. size and access a ski boot size chart online for its Mondopoint equivalent. Other option are to measure the foot in centimeters or to use the addition formula.
In order to figure out the equivalent U.S. size without a ski boot sizing chart, the addition formula of adding the two digits of the Mondopoint size together can be used. When using the addition formula, keep in mind most metric sizes do not carry fractions and therefore may be a whole size or size range. If the Mondopoint size is above 30, add 9 to the total. For example, if the Mondopoint size is 31, the formula would become 3 plus 1 plus 9, equaling a U.S. men's size 13. To adjust for women's sizing, add 1.5 to the total to determine the U.S. women's size equivalent.