Sock Size Calculator: Find Your Size by Foot Length or Shoe Size
Enter your foot length or shoe size and this calculator instantly returns your sock size in US, UK, and EU formats, plus the commercial label (Small, Medium, Large) printed on most sock packaging. Switch between metric and imperial units or enter a shoe size from any system and the calculator converts it for you.
What is a sock size and how is it measured?
Unlike shoe sizing, which varies widely between countries and manufacturers, the US numeric sock size is a direct measurement: it equals your foot length in inches, rounded to the nearest half-inch. So a foot that is 10.3 inches long takes a US sock size 10.5. This makes the system unusually intuitive once you know your foot length. The UK system is the same measurement but labelled one number lower (US 10 = UK 9). The European system uses the Paris point scale, where one unit equals two-thirds of a centimetre, so EU sock size equals foot length in centimetres multiplied by 1.5.
How to measure your foot at home
The most accurate method is the paper-trace technique. Place a sheet of paper on a hard floor, stand on it with your heel against a wall, and mark the tip of your longest toe. Measure the distance from the wall to the mark in centimetres or inches. Do both feet and use the longer measurement. Wear the type of sock you intend to measure for (thin dress socks vs thick wool socks) because sock thickness affects the shoe-sock fit. A Brannock Device at a shoe shop gives the same measurement professionally. Avoid measuring on carpet, which compresses under foot weight and produces a slightly short reading.
From shoe size to sock size: how the conversion works
Shoe sizes follow the Brannock Device scale, which assigns a size number based on foot length in barleycorns (one barleycorn = 1/3 inch) in the US system, or in the equivalent Paris point scale for EU shoes. Because the relationship is linear, each shoe size step corresponds to roughly 1/6 inch (about 4.2 mm) in the US system. The calculator looks up the standard Brannock foot-length for your shoe size and then converts that to the corresponding sock size. Note that shoe sizes include a small toe allowance (roughly half a size), so your true foot length is slightly shorter than the shoe length. The calculator accounts for this in the lookup table.
Why sock sizes overlap: the "one-size" and range labels
Most commercially packaged socks use a range such as "9-11" or "10-13" rather than a single size. This is because knitted fabric stretches, so one knitted tube can comfortably accommodate several foot lengths. The range tells you the minimum and maximum foot lengths (in inches) the sock is designed to fit without being too loose or so tight that it restricts circulation. Choosing the tighter end of a range gives a closer, athletic-style fit; choosing the wider end gives a more relaxed feel. For people whose foot sits between two ranges, personal preference and intended use (running vs casual) guide the choice.
Adult sock size conversion chart (US, UK, EU)
| Foot length | US sock size | UK sock size | EU sock size | Commercial label |
|---|---|---|---|---|
| < 22.9 cm / < 9.0 in | < 9 | < 8 | < 34 | Extra Small |
| 22.9-27.9 cm / 9.0-11.0 in | 9-11 | 8-10 | 34-42 | Small / Medium |
| 25.4-33.0 cm / 10.0-13.0 in | 10-13 | 9-12 | 39-49 | Medium / Large |
| 33.0-38.1 cm / 13.0-15.0 in | 14-15 | 13-14 | 49-57 | Large / X-Large |
| > 38.1 cm / > 15.0 in | 16+ | 15+ | 57+ | Extra Large |
Standard commercial size bands used by most hosiery brands. Individual brands vary slightly.
Frequently asked questions
How do I find my sock size from my shoe size?
Select your shoe system (US, UK, or EU) in the "Find size by" dropdown, enter your shoe size, and the calculator looks up your foot length from the standard Brannock scale, then converts it to US, UK, and EU sock sizes. For the most accurate result, use foot length mode with a direct measurement instead.
What does a sock size like "9-11" mean?
The two numbers are the minimum and maximum foot lengths in inches that the sock is designed to fit. A sock labelled "9-11" stretches to fit any foot between 9 and 11 inches long. If your foot is 10 inches long, it sits in the middle of that range and will fit comfortably.
What is the difference between US and EU sock sizing?
US sock size equals foot length in inches rounded to the nearest half-inch. EU sock size uses the Paris point scale, where each unit equals two-thirds of a centimetre, so EU size = foot length in cm times 1.5. A US size 10 (10-inch foot, about 25.4 cm) corresponds to EU size 38-39.
Do men and women have different sock sizes?
The sizing numbers themselves are the same system (foot length in inches), but the shoe-size-to-foot-length tables differ between men and women because US shoe sizes for men and women are assigned on different scales. If you enter your foot length directly, gender does not matter. If you enter a shoe size, the calculator uses the correct men's or women's shoe-to-foot-length table.
How do I size kids socks?
Select "Child" in the age group field. Children's sock sizes are labelled differently from adult sizes, often by age range (Infant, Toddler, Child, Youth) rather than by foot-length inches. The calculator converts child shoe size to foot length and then maps it to the appropriate children's band. Because children's feet grow quickly, re-measure every few months.
What if my foot length puts me between two size bands?
Most knitted socks fit a range of sizes, so being between bands is rarely a problem. If you are between a Small/Medium (9-11) and a Medium/Large (10-13), and both claim your foot size, choose the smaller band for a snug fit or the larger band for a looser, cushioned feel. For compression socks or socks with precise arch support, choose based on the brand's specific guide.
Are sock sizes the same as shoe sizes?
No. US shoe sizes and US sock sizes are related but not identical. A US shoe size 10 for men does not mean your sock size is 10. Sock sizes are based directly on foot length in inches (shoe size 10 in men corresponds to a foot roughly 10.75 inches long, which maps to sock size 11). This calculator handles the conversion for you.