Enter the foot length into the calculator to determine the sock size. This calculator can also evaluate any of the variables given the others are known.

Sock Size Formula

The following formula is used to calculate the sock size.

SS = (F * 1.5) 


  • SS is the sock size F is the foot length in inches

To calculate the sock size, multiply the foot length in inches by 1.5. The result is the sock size.

What is a Sock Size?

A sock size refers to the measurement that corresponds to the length of your foot from heel to toe. It is used to determine the right fit for socks, similar to how shoe sizes work. Sock sizes can vary between brands and countries, and they may be displayed in different units of measurement such as inches, centimeters, or as a general small, medium, large, etc. It’s important to know your sock size to ensure comfort and prevent damage to your feet.

How to Calculate Sock Size?

The following steps outline how to calculate the Sock Size using the formula: SS = (F * 1.5).

  1. First, determine the foot length in inches (F).
  2. Next, multiply the foot length by 1.5.
  3. Finally, calculate the Sock Size (SS).
  4. After inserting the foot length and calculating the result, check your answer with the calculator above.

Example Problem:

Use the following variables as an example problem to test your knowledge.

foot length (F) = 10 inches