Sock sizes should be simple, so we kept ours simple: one size for women, one size for men. Each is knitted to fit the full span of adult feet it is made for, so there is nothing to work out beyond which of the two you are. The complicated part is the rest of the world, where three different systems are used to measure the same foot. Here is how they relate, how to find your size in any of them, and how to read it against ours.

One size for women, one size for men

Every sock we make, cotton, merino or cashmere, ankle or crew, comes in exactly two sizes. Women's socks fit EU 36 to 41. Men's socks fit EU 40 to 46. Pick the one that matches your shoe size and you are done. The one exception is our unisex tube socks, which have no shaped heel and so stretch across both ranges in a single size.

One detail on cashmere. The cashmere and wool blend stretches less than cotton, so the men's cashmere size covers EU 41 to 45 (UK 7 to 10.5, US 8 to 11.5) rather than 40 to 46. It is still the one men's size, just with a slightly narrower span. The women's cashmere size is the same EU 36 to 41 as the rest of the women's range.

If your shoe size falls inside one of those ranges, that is your sock. If you sit at the overlap, EU 40 or 41, both will fit and there is a note further down on how to choose.

Why there are three systems

Each system measures the inside length of a shoe, but each uses a different unit and a different starting point, which is why the numbers look unrelated.

EU (Paris point). One size equals two thirds of a centimetre. The scale starts at zero, so an EU 42 is simply a shoe 28 centimetres long inside. It is the most consistent of the three and the one we use as our base.

UK (barleycorn). One size equals a third of an inch, a unit that dates back to a fourteenth century decree that three barleycorns make an inch. The scale starts at a children's size zero, with adult sizes continuing the count. Half sizes are common.

US. Same barleycorn unit as the UK, but with a different starting point, and a different offset for men and women. Roughly, a US men's size is one bigger than the UK size for the same foot, and a US women's size is about two and a half bigger than the UK size. So a UK 7 is a US men's 8 and a US women's 9.5. This is the part that catches people out when they shop across the Atlantic.

None of this is standardised between brands. A shoe brand's 42 is not always another brand's 42, and sock makers inherit that inconsistency. The table below is the accepted conversion, and it is accurate to within half a size.

Full conversion table

Foot length is the measurement to trust if you can take it. Shoe sizes drift from brand to brand; centimetres do not.

How to measure your foot

1. Stand on a sheet of paper against a wall, heel touching the wall, with your weight on that foot.
2. Mark the tip of your longest toe. It is not always the big one.
3. Measure from the edge of the paper to the mark in centimetres.
4. Do the other foot. Use the longer of the two.

Then read across the table. There is no need to add anything for socks; the sock will stretch to the foot.

Why one size can cover six shoe sizes

A knitted sock stretches, so one size can fit several foot lengths comfortably. That is why we can make a single women's size and a single men's size rather than a sock for every number, and why the label says 40 to 46 rather than 43. What the range tells you is the span over which the heel pocket lands in the right place and the toe is neither baggy nor strained. Keeping it to two sizes also means every colour is always in stock in your size, which is not true of brands that split their range into five.

Inside the range, the fit changes a little. At the small end the sock has more fabric to spare and sits a touch looser. At the large end it is fully stretched, the heel sits slightly high and the toe is under tension. Neither is a problem within the stated range. Outside it, the sock is either slouching at the ankle or wearing thin at the toe, which is where most holes start.

At the overlap

The women's size runs to EU 41 and the men's size starts at EU 40, so if you are a 40 or a 41 you can wear either.

Women with an EU 41 or 42 foot. The women's size will fit, but it is at the top of its range. If you like a sock with a bit of ease, or you have a high instep, the men's size will sit more comfortably. The only difference is the span of the fabric; the yarns and the colours are the same across both.

Men with an EU 40 foot. The men's size will fit well. If your foot is narrow, the women's size is a good alternative for a closer fit.

When in doubt, go up. A slightly roomy sock lasts longer than a tight one.

Ankle socks, crew socks, cashmere and tube socks

The length of the leg does not change the size you need. An ankle sock and a crew sock in the same size fit the same foot; only the leg differs. Cashmere is the same women's or men's size, with the slightly narrower men's span noted above, because the yarn gives less. Tube socks are the one true exception. They have no shaped heel, so one size stretches to a much wider span of feet, which is why ours run from EU 36 to 45 in a single unisex size.

A note for US and UK customers

Most of our customers are in the United States and the United Kingdom, and most sizing mistakes we see are a US size read as a UK size, or the other way round. The numbers are close enough to look right and far enough apart to be wrong by a full size. Every product page shows all three systems side by side. Match the one you know and ignore the rest.

If a pair still does not fit, write to us and we will sort it out.

Questions we are asked

How do you convert EU sock sizes to UK sizes?
Take roughly 33 to 34 off the EU size: EU 38 is UK 5, EU 42 is UK 8 and EU 44 is UK 10. The two systems count in different units, so the difference is not quite constant and a chart is the safest way to check.

What is the difference between US and UK sock sizes?
A US men's size is about one size larger than the UK size for the same foot, and a US women's size about two and a half sizes larger. So a UK 7 is roughly a US men's 8 and a US women's 9.5.

Should you size up or down in socks?
Buy socks for the shoe size you already wear; a knitted sock stretches to the foot, so there is nothing to add. If you sit between two sock sizes, go up: a slightly roomy sock lasts longer than one stretched tight.

How do you measure your foot for socks?
Stand on a sheet of paper with your heel against a wall, mark the tip of your longest toe and measure the distance in centimetres. Do both feet, use the longer one, then read that length against a size chart.

What size are Escuyer socks?
Escuyer makes one women's size, EU 36 to 41 (UK 3.5 to 7.5), and one men's size, EU 40 to 46 (UK 6.5 to 11, US 7.5 to 12). Men's cashmere runs EU 41 to 45, and the unisex tube socks fit EU 36 to 45.

Escuyer. Considered design, made to last.