When you fall between two sock sizes

Short answer: Choose the larger size. A sock stretched to its limit becomes thinner, wears out faster and presses over the toes.

Stretching costs thickness

When the knit is stretched out, the fabric becomes thinner exactly where you need it most, at the heel and under the foot. A sock already stretched to the limit offers less padding from the very first time you wear it. See bamboo socks for men.

The toe box feels it first

A sock that is too small squeezes the toes together and becomes noticeable after an hour in closed shoes, especially if you stand or walk a lot. The discomfort often starts at the little toe and spreads until you have to change socks mid day. See bamboo tennis socks for men.

Too big is only a problem in shoes

A slightly too large sock folds inside the shoe and can create a fold under the foot. At home it makes no difference, but in a sneaker or running shoe the fold can turn into a chafing edge after a couple of hours of walking.

The heel shape reveals the right size

Most socks have a shaped heel that should sit exactly on your own heel. If the shape sits too high or too low, the size is wrong, no matter what the shoe size range on the package says.

The material's stretch changes how it feels

A knit with a lot of stretch adapts better than a stiff knit, which is why two socks in the same stated size can feel completely different. Always test a new style even if you normally know your size.

Wash heat wears down the fit over time

The elastane in a sock loses tension with repeated hot washing, and a sock that fit perfectly six months ago may now be too loose. Always follow the wash instructions to keep the fit for as long as possible.

The thickness should match the shoe

A thin sock in a roomy winter boot leaves extra space, which can feel like the wrong size even though the sock itself is correct. Always match the sock's thickness to the shoe's roominess to avoid misjudging the size.

Switch between two sizes depending on purpose

Some people choose one size for sport and another for everyday wear on purpose, because the need for stretch and padding differs. The same goes for both men's and women's styles, see bamboo socks for women. This is a completely normal solution if you fall between two sizes in the stated chart.

Always try both sizes when in doubt

When you fall between two sizes, the safest solution is to try both and walk in them for at least half an hour. The one that does not press over the toes or slip at the heel is the right one.