Select your gender and enter the total measurement of your foot in inches into the calculator. The calculator will evaluate your shoe size based on the length of your foot and sex.

Shoe Size Formula

The following three formulas are used to calculate your shoe size based on your foot length.

USM= (3 * L) – 22

USF= (3 * L) – 21

USC= (3 * L) – 9.67

  • Where L is the length in inches
  • USM is men’s size
  • USF is females size
  • USC is children’s size

Shoe Size Definition

A shoe size is a standard way of displaying the length of a shoe so that people can more easily understand the proper size to use for their feet.

Shoe Size Example

How to calculate shoe size

  1. First, measure your foot

    Measure the length of your foot from heel to toe in inches.

  2. Select the proper formula

    Select the correct formula from above based on your gender.

  3. Calculate your shoe size

    Using the length of your foot and inches, and the equation above, calculate your proper shoe size.


What is a shoe size?

A shoe size is a standard measure of unit used for estimating the size of a shoe. The reason for shoe sizes is so that individuals can purchase shoes that will fit their feet as best as possible.