Sock Size Calculator

Enter your foot length to get your US sock size number, the standard package size range to look for, and the matching US shoe size.

Quick Facts

How sock sizing works
Sock size number = foot length in inches
Traditional US hosiery numbering rounds foot length to the nearest half inch, then packages it into a labeled range like "9-11" or "10-13".

Your Results

Calculated
US Sock Size
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Foot length in inches, nearest half size
Sock Size Range to Buy
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Standard package labeling
Equivalent Shoe Size
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US sizing, for reference
Measured Foot Length
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Converted to both units

Ready

Enter your foot length and press Calculate to see your sock size.

About the Sock Size Calculator

This tool converts a measured foot length into a US sock size using the traditional hosiery-industry numbering convention: sock size is simply your foot length in inches, rounded to the nearest half size. That single number is then bracketed into the range printed on most sock packaging — such as "9-11" or "10-13" — along with the roughly equivalent US shoe size.

The formula

Given a foot length measured heel to longest toe:

  • US Sock Size = foot length in inches, rounded to the nearest 0.5. A 10-inch foot is sock size 10; a 10.7-inch foot rounds to sock size 10.5.
  • Package range: manufacturers group sock sizes into labeled bands. Common US bands are roughly 9-11 for a smaller/women's foot, 10-13 for a mid-to-large or men's foot, and 13-15 for an extra-large foot. Because the same numeric size can appear in more than one band, this calculator uses your chosen sizing convention (men's, women's, or unisex) to pick the closest match.
  • Equivalent US shoe size: using the common reference that a 26 cm foot is about US Men's shoe size 8 (each additional whole men's size is roughly 1 cm of foot length, and US women's sizing runs about 1.5 sizes higher than men's for the same foot length), so US Men's ≈ foot length (cm) − 18, and US Women's ≈ that value + 1.5.

How to measure your foot

Stand on a sheet of paper with your heel against a wall, mark the tip of your longest toe (not always the big toe), then measure the distance from the wall to that mark. Measure both feet — most people have one foot slightly longer — and use the longer one. Measure later in the day when feet are typically at their largest, since feet swell somewhat over the course of a day.

Why sock sizing looks different from shoe sizing

Shoe sizes use their own numbering scale that does not start at zero foot length, so a men's shoe size 8 does not mean an 8-inch foot — it is closer to a 10.2-inch foot. Sock sizing skips that translation and numbers directly by foot length, which is why a package might say "Sock Size 10-13" even though the shoes that fit the same feet are numbered 6 to 12.5.

Frequently Asked Questions

How is sock size calculated from foot length?
The traditional US hosiery numbering sizes socks directly by foot length in inches, rounded to the nearest half size. A 10 inch foot is sock size 10. Manufacturers then bracket that number into a printed range such as 9-11 or 10-13 on the package label.
Why do men's and women's sock sizes differ for the same foot length?
The underlying number is just foot length, but packaging brackets differ by target group. Women's socks are commonly labeled 9-11, covering roughly a women's shoe size 4 to 10, while men's socks are commonly labeled 10-13, covering roughly a men's shoe size 6 to 12.5. The same foot length can fall inside either labeled range depending on which convention the package uses.
How do I measure my foot for sock sizing?
Stand on a sheet of paper with your heel against a wall, mark the tip of your longest toe, then measure the distance from the wall to that mark in inches or centimeters. Measure both feet, use the longer measurement, and measure later in the day when feet are at their largest.
Is sock size the same as shoe size?
No. Sock size is a direct foot-length measurement in inches, while US shoe size uses its own numbering scale with a different starting point. A men's shoe size 8, roughly a 26 cm foot, works out to about sock size 10, not sock size 8.

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