Sock size chart
Sock sizes are really shoe size ranges. This chart maps each sock size to the US men's and women's shoe sizes it fits, the EU range and the foot length.
| Sock size | US Men shoe | US Women shoe | EU shoe | Foot (cm) |
|---|---|---|---|---|
| S | 5 to 7 | 6 to 8 | 38 to 40 | 23 to 24.5 |
| M | 7.5 to 9 | 8.5 to 10 | 40.5 to 42.5 | 25 to 26.5 |
| L | 9.5 to 12 | 10.5 to 13 | 43 to 46 | 27 to 29 |
| XL | 12.5 to 15 | 13.5 to 16 | 46.5 to 49 | 29.5 to 31.5 |
What the number on the packet means
Socks are rarely labelled S, M or L on the packet. They are labelled with the shoe range they fit, printed as a span like 9 to 11. This is the same chart read the way a packet is written, so you can match a label in a shop to a letter size.
| Printed on the packet | Letter size | US Women shoe | EU shoe | Foot (cm) |
|---|---|---|---|---|
| 5 to 7 | S | 6 to 8 | 38 to 40 | 23 to 24.5 |
| 7.5 to 9 | M | 8.5 to 10 | 40.5 to 42.5 | 25 to 26.5 |
| 9.5 to 12 | L | 10.5 to 13 | 43 to 46 | 27 to 29 |
| 12.5 to 15 | XL | 13.5 to 16 | 46.5 to 49 | 29.5 to 31.5 |
The number on a packet is almost always the US men's shoe range, even on socks sold as unisex. If you wear US women's sizes, read the third column rather than the first, or the sock will come up a size and a half large.
Kids sock sizes
Children's socks are sold in bands that follow the shoe chart rather than in letters. The table below is derived from the kids shoe chart on this site, so the foot lengths are the same numbers used there and nothing is estimated separately.
| Sock band | US shoe range | EU shoe range | Foot (cm) | Indicative age |
|---|---|---|---|---|
| Baby | 0 to 4 | 15 to 19.5 | 8.3 to 11.7 | 0 to 9 to 12 months |
| Toddler | 4.5 to 10 | 20 to 27 | 12.1 to 16.6 | 12 to 4 years |
| Youth | 10.5 to 7Y | 27.5 to 39 | 17.1 to 25 | 4 years to 12 plus years |
Ages are indicative only. Children of the same age can be several sizes apart, so match the foot length rather than the age on the packet. See the kids shoe size chart for the size behind each band.
Sock sizes look mysterious because they are printed as their own small range like 9 to 11, but they are really just shoe size bands. A sock size covers a span of shoe sizes and, underneath, a span of foot lengths, so the same pair fits several neighbouring shoe sizes.
The chart below maps each sock size to the US men's and women's shoe ranges it fits, the EU shoe range and the foot length in centimetres, so you can pick socks correctly whether you shop by US, EU or your measured foot.
Sock size questions
What sock size am I?
Match your shoe size to the chart. A US men's 7.5 to 9 or women's 8.5 to 10 is a medium sock, which is EU 40.5 to 42.5. Sock sizes cover a range, so exact shoe size is not critical.
What does a sock size like 9 to 11 mean?
That range is the span of US shoe sizes the sock is designed to fit. The stretch in the knit lets one sock size cover several shoe sizes comfortably.
Do socks come in EU sizes?
Yes. European socks are often labelled by the EU shoe range they fit, for example 43 to 46 for a large. The chart lines up US, EU and foot length so you can convert.
Is the range on the packet a men's or a women's shoe size?
Almost always men's, even on socks sold as unisex. If you wear US women's sizes and buy by the printed number, the sock will come up about a size and a half large. Read the US women's column in the chart instead.
What sock size does a child need?
Children's socks are sold in bands that follow the shoe chart rather than in letters: a baby band, a toddler band and a youth band. Match the foot length rather than the age printed on the packet, because children of the same age can be several sizes apart.
What if my foot falls between two sock sizes?
Take the smaller one for everyday socks, since the knit stretches and a sock that is slightly long bunches at the toe. Take the larger one for compression and athletic socks, where the heel pocket has to sit in the right place and a tight sock puts it in the wrong one.
Is there a standard for sock sizes?
We know of no published international standard for sock sizes. The numeric ranges are shoe-size spans in the US men's scale, which is why this chart maps them straight back to shoe size and foot length rather than to another manufacturer's letter.
Where these numbers come from
Every row in this chart is anchored to the length of the foot in centimetres, the same anchor as shoe sizes. Sock sizes cover ranges rather than points, so a foot at the edge of a range fits either the smaller or the larger size depending on how much the knit stretches.
What is not standardised. We know of no published standard for sock sizes. The numeric sock sizes still printed on some packaging (9 to 11, 10 to 13) are shoe-size ranges in the US men's scale, which is why this chart maps them straight back to shoe size.
Reviewed by Jamey Weber, last checked August 5, 2026. Found an error? Report it and it gets fixed in the changelog. See also the full methodology.
Last reviewed and updated on August 5, 2026. Conversion tables are checked against published international sizing standards.