Enter your measured foot length (or US Men’s shoe size) to convert between them, and enter your measured foot width to convert units. Note: US shoe size is primarily based on length, and shoe width is normally specified separately using width codes (e.g., D, EE) that vary by brand—there is no single universal formula that can determine foot width from shoe size and foot length alone.

Foot Width Calculator

Enter a foot length or a US Men’s shoe size to estimate the other (approx.). Enter foot width to convert units and view the value in inches in the steps.

Related Calculators

US Men’s Shoe Size vs. Foot Length (Approximate Formula)

US men’s shoe size is primarily based on foot length. A commonly used approximation in sizing charts relates US men’s size to foot length in inches (exact fit can vary by brand/last):

SS \approx 3 \cdot FL_{in} - 22

The inverse relationship is:

FL_{in} \approx \frac{SS + 22}{3}

Variables:

  • SS is the US Men’s shoe size
  • FLin is the foot length in inches

Foot width note: Foot width is not uniquely determined by shoe size and foot length. Shoe widths are typically given as width codes (for example, D, EE) and the mapping between codes and inches varies by brand and model. For best results, measure foot width directly and consult the specific brand’s width chart.

What is Foot Width?

Foot width is a measurement that indicates how wide a person’s foot is across the widest part. It is an important measurement for finding comfortable and well-fitting shoes. Foot width can vary significantly from person to person and is not always proportional to foot length or shoe size.

How to Calculate Foot Width?

The following steps outline how to determine (measure) foot width.

  1. Stand on a sheet of paper with your full weight on the foot you are measuring (wear the type of socks you plan to use).
  2. Mark the widest points of your forefoot (across the ball of the foot) and measure the distance between the marks to get your foot width (FW).
  3. Measure foot length (FL) from the back of the heel to the longest toe.
  4. Use the calculator above to convert your measured width and length between units, and (optionally) estimate US Men’s shoe size from your measured length.
  5. For shoe shopping, compare your measurements to the specific brand/model sizing chart (width codes and fit vary by manufacturer).

Example Problem:

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

Foot length (FL) = 10.5 inches

Estimated US Men’s shoe size (SS) ≈ 3 × 10.5 − 22 = 9.5

Measured foot width (FW) = 4.0 inches (which is 4.0 × 2.54 = 10.16 cm)