Updated November 2026 · By Socks That Pop
Quick answer: sock sizes follow your shoe size, and the number on a sock label is roughly the length of your foot in inches. Most adults fit a sock size 9–11 (about women's US shoe 4–10) or 10–13 (about men's US shoe 6–12). Letter sizes (S, M, L, XL) vary by brand, so always check the brand's own socks size chart. Our printed crew socks at Socks That Pop are one size and fit women's US 5 to men's US 12.
If you have ever stood in a store holding a pack labelled "10–13" and wondered whether that is your shoe size, you are not alone. Below you will find an adult chart with US, UK and EU sizes, a chart in centimeters, kids and boys sock sizes, how to measure your foot at home, and what to do if you fall between two sizes.
Jump to: Adult sock size chart · Socks size chart in cm · Kids socks size chart · Boys socks size chart · How to measure · Our socks · FAQ
Adult Sock Size Chart (US, UK & EU)
This chart shows the sock sizes most US brands use for adults, matched to shoe sizes. Use it as a starting point: a few brands shift each range by half a size, and athletic or compression socks are often sized more tightly.
| Letter size | US women's shoe | US men's shoe | UK shoe | EU shoe | Sock size (number) |
|---|---|---|---|---|---|
| S | 4–6 | – | 2–4 | 35–37 | 8–9 |
| M | 6–9 | 5–8 | 4–7 | 37–41 | 9–11 |
| L | 9–12 | 8–12 | 7–11 | 41–46 | 10–13 |
| XL | – | 12–15 | 11–14 | 46–49 | 13–15 |
A few things to notice:
- The ranges overlap on purpose. Knit socks stretch, so a women's size 9 can wear either an M or an L depending on the brand and how snug they like it.
- "Sock size" and "shoe size" are different numbers. A sock labelled 10–13 does not mean shoe size 10–13. It is the sock size, which in the US usually covers men's shoes 6–12.
- Women's and men's shoe sizes are about 1.5 sizes apart. A women's US 8.5 is roughly a men's US 7, so a unisex sock can cover both if the range is wide enough.
What Does a Sock Size Number Mean?
In the US and UK, the number on a sock label is based on foot length. A sock size 10 is designed for a foot about 10 inches long, a size 11 for about 11 inches, and so on. Because socks stretch, packs are usually sold as a range such as 9–11 or 10–13 instead of a single number.
This is also why kids' socks have small numbers (5–6, 6–7) and adult men's "big and tall" socks go up to 13–15. Once you know your foot length, you can read almost any label without a chart.
Socks sizes by type of sock
Sizing also shifts a little depending on what you are buying:
- Crew socks (like ours) have the most stretch in the leg and cuff, so a single size can fit a wide range of feet.
- Dress socks are thinner and often sold in "fits shoe size 7–12" ranges.
- Compression or performance socks are usually sized by both shoe size and calf measurement, so follow the brand chart exactly.
- Wool and hiking socks can shrink slightly if washed hot, so many people size up if they sit at the top of a range.
Socks Size Chart in CM
Outside the US, and on many international product pages, socks are sized by foot length in centimeters or by EU shoe size. Here is a simple conversion. Measure your foot (instructions below), then find the closest row.
| Foot length (cm) | Foot length (in) | Sock size (US/UK) | Approx. EU shoe |
|---|---|---|---|
| 20.5–22 | 8–8.6 | 8–8.5 | 33–35 |
| 22–23.5 | 8.7–9.2 | 9 | 35–37 |
| 23.5–25 | 9.3–9.8 | 9.5–10 | 37–40 |
| 25–26.5 | 9.9–10.4 | 10–10.5 | 40–42 |
| 26.5–28 | 10.5–11 | 11 | 42–44 |
| 28–29.5 | 11.1–11.6 | 11.5–12 | 44–46 |
| 29.5–31 | 11.7–12.2 | 12–13 | 46–48 |
| 31–33 | 12.3–13 | 13–14 | 48–50 |
Tip: one inch is 2.54 cm, so if a brand lists a sock size, you can multiply it by 2.54 to get the approximate foot length it is designed for. A size 11 sock is made for a foot of about 28 cm.
Kids Socks Size Chart
Children's feet grow fast, so kids' socks are usually sold by age or by kids' shoe size. The chart below shows typical US ranges. Ages are only a guide: two five-year-olds can easily be two shoe sizes apart, so the shoe size column is more reliable.
| Approx. age | US kids' shoe size | Sock size | Foot length (cm) |
|---|---|---|---|
| 0–6 months | 0–2 | 3–4 | 8–10 |
| 6–12 months | 2–4 | 4–5 | 10–12.5 |
| 1–3 years (toddler) | 4–7 | 5–6 | 12.5–15 |
| 3–5 years | 7–10 | 6–7 | 15–17.5 |
| 5–8 years | 10–13 | 7–8.5 | 17.5–20.5 |
| 8–12 years | 13–4 (big kid) | 8.5–9.5 | 20.5–23 |
For babies and toddlers, choose socks with a little room in the toe. Tight socks on small feet tend to slip off or leave marks, and little ones cannot tell you when something feels wrong. Check the fit every few months, since a toddler can move up a size in a single season.
Boys Socks Size Chart
Boys' socks are often sold in letter sizes that cover a range of shoe sizes. Exact ranges differ between brands, but many follow a pattern like this:
| Boys' letter size | US shoe size | Approx. age |
|---|---|---|
| XS | Toddler 7–10 | 3–5 years |
| S | Little kid 10.5–13 | 5–7 years |
| M | Kids 13.5–4 | 7–10 years |
| L | Youth 4–7 | 10–14 years |
| XL | Youth 7–10 / men's 7–9 | Teens |
Once a boy reaches a youth shoe size of around 6 or 7, he can usually move into adult small or medium socks, which is roughly where women's US 5 begins. Girls' socks follow the same shoe-size logic, though some brands label them differently, so check the chart on the pack.
A note on our range: Socks That Pop does not make kids' socks right now. Our printed crew socks are adult one-size, so they are best for teens and adults whose shoe size is at least women's US 5.
How to Measure Your Foot for Socks
Measuring takes two minutes and is the most accurate way to use any socks size chart, especially if you are buying for someone else or switching between US and EU sizes.
- Stand on a sheet of paper on a hard floor, heel against a wall. Stand normally with your weight on the foot.
- Mark the tip of your longest toe with a pencil held straight up. Ask someone to help if you can.
- Measure from the wall to the mark in centimeters or inches.
- Repeat with the other foot. Most people have one foot slightly longer. Use the longer measurement.
- Find your row in the cm chart above, or compare the length in inches with the sock size number.
Measure in the afternoon or evening if you can. Feet tend to be slightly bigger later in the day, which gives you a more realistic fit for all-day wear.
How Should Socks Fit?
A well-fitting sock should feel snug but never tight. Check these points when you try a pair on:
- Heel: the heel pocket should sit right on your heel. If it rides up onto your ankle, the sock is too small. If it slides under your foot, it is too big.
- Toes: there should be no loose fabric bunching at the toe, and the seam should not press into your toenails.
- Cuff: the top should hold the sock up without leaving deep marks on your leg.
- Arch: the sock should lie flat with no twisting, wrinkles or sagging.
What if you are between sizes?
If you sit right on the line between two sizes, think about the sock and how you wear it:
- Choose the smaller size for athletic socks or if you like a firm, secure fit.
- Choose the larger size for thick winter socks, wool socks, or if you have wide feet or high arches.
- For stretchy one-size crew socks, you usually do not need to choose at all, as long as your shoe size sits inside the stated range.
Socks that are too small wear out faster at the heel and toe because the yarn is stretched thin. Socks that are too big bunch in your shoes and can rub. Getting the size right makes a pair last longer, which matters when you love the design.
Socks That Pop Sizing: One Size, Explained
Every pair in our socks collection is a cushioned 3/4 crew sock in one adult size. Here is what that means in practice:
| Detail | Socks That Pop crew socks |
|---|---|
| Size | One size, US adult |
| Fits | Women's US 5 to men's US 12 (about UK 3–11, EU 35/36–46) |
| Length | 3/4 crew (sits above the ankle, below the calf) |
| Material | 73% polyester, 18% nylon, 6% spandex, 3% cotton |
| Comfort | Cushioned heel-to-toe sole |
| Price | $17.99 per pair |
The spandex in the blend is what lets one size fit such a wide range: the knit stretches to fit a larger foot and springs back on a smaller one. If you wear a men's 13 or larger, our socks will feel tight, and we would rather tell you that now than have you disappointed.
Popular pairs to try
Because size is never the problem, you can pick purely on design. A few customer favorites, all $17.99:
- Striped Crew Socks – candy-colored stripes that go with jeans, leggings and sneakers.
- Pastel Star Crew Socks – soft multicolor stars on white, a sweet gift for dreamers.
- Panda Crew Socks – pandas and bamboo for animal lovers.
- Blue Argyle Crew Socks – a classic diamond pattern that works with chinos and loafers.
- Pink Checkered Crew Socks – retro gingham in pink.
- Tuxedo Wedding Socks – a fun groomsmen gift that fits the whole wedding party in one size.
Looking for more ideas by person? See our guides to cute socks for women, fun socks for men and cat and animal socks.
Buying Socks as a Gift Without Knowing Their Size
Socks are one of the most popular stocking stuffers for a reason, but size can still trip you up. A few easy ways around it:
- Pick one-size crew socks. A pair that fits women's 5 to men's 12 covers most adults, so you only need to think about the design.
- Peek at their shoes. The size is usually printed on the tongue or insole of sneakers.
- Ask a partner or roommate. They often know, or can check without spoiling the surprise.
- Remember the 1.5 rule. If you only know a women's size, subtract about 1.5 to get the men's size, and vice versa.
Shopping for the holidays? Our Christmas socks gift guide has stocking stuffer ideas, and the Christmas collection has hoodies and sweaters to pair with a festive pair. If the gift is for a cozy night in, a comfortable pair of socks and one of our hoodies make a great bundle, and our new guide on how to wear oversized hoodies shows how to style them together.
Caring for Socks So They Keep Their Size
Heat is the main reason socks lose their shape. To keep a pair fitting like new:
- Machine wash cold (max 30°C / 90°F), inside out, with similar colors.
- Skip bleach and fabric softener, which can weaken stretch fibers.
- Air dry instead of tumble drying. Our printed socks are labelled do not tumble dry, and the dryer is the fastest way to shrink or loosen elastic.
- Do not iron printed socks.
Washing printed socks inside out also protects the colors from rubbing against zips and buttons in the drum.
Sock Size FAQ
What size socks do I need for shoe size 9?
A women's US 9 usually fits a sock size 9–11 (medium) or 10–13 (large). A men's US 9 fits sock size 10–13. Our one-size crew socks fit both.
What does sock size 10–13 mean?
Sock size 10–13 is the most common men's sock range in the US. It usually fits men's shoe sizes 6–12 and women's shoe sizes of about 8–12.
Are sock sizes the same as shoe sizes?
No. Sock size numbers are based on foot length in inches, so they are usually smaller numbers than adult shoe sizes. Always check which size the label refers to.
What size is a "one size fits most" sock?
It depends on the brand. For Socks That Pop, one size means women's US 5 to men's US 12. Other brands may use a narrower range, so check the product page.
How do I convert EU sock sizes to US?
EU socks are usually listed by shoe size ranges such as 39–42. Find your EU shoe size, then use the adult chart above to match it to a US shoe size and sock size.
Should I size up in socks?
Size up if you sit at the top of a range, have wide feet, or are buying thick wool socks. For stretchy crew socks, stick with the stated range.
Find Your Pair
Now that you know your size, the fun part is choosing a design. Browse the full Socks That Pop socks collection: every pair is one size, $17.99, and printed with designs made to get noticed. If you are wondering about wearing them to bed this winter, read our guide on sleeping with socks on.
About the author: Socks That Pop designs bold printed socks, hoodies, tees and more for people who like their wardrobe with personality. Size charts in this guide are general guidance based on common US sizing; always check the chart on the specific product you buy.
