Why socks rarely come in half sizes
Short answer: A sock stretches by thirty to fifty percent. That is why one pair can cover several shoe sizes, and half steps would not be felt on the foot. Fewer sizes also keep stock and price down.
The stretch makes the steps unnecessary
A sock adapts to the foot because the yarn contains elastic and the stitches stretch and pull back. The difference between size forty two and forty two and a half disappears in the stretch, long before you can feel it. That is the main reason socks rarely come in half sizes.
How small a half size really is
A half shoe size is a difference of less than a centimetre in foot length. The sock is knitted to sit with some tension, so a gap that small is absorbed by the material without folds or pressure. Two socks that differ by only half a step would be impossible to tell apart.
Fewer sizes cost less
Every size needs its own machine setting and its own stock. Three or four ranges cover almost every foot and keep the price down, because fewer variants must be knitted, packed and stored. If every half size had its own pair, the sock would cost more without feeling better. See bamboo socks for women.
It keeps stock simpler
With few ranges, each size can be held in larger quantities, so it sells out less often. A shop that had to shelve every half size would need to order far more or accept gaps in the range. For a sock that fits several feet anyway, splitting it up further makes little sense.
How to find your range
Measure your foot from heel to longest toe, or use the size of the shoes you wear most. Then find the range that number falls in. If you sit in the middle of a range the fit is most even, while a number at the edge can feel slightly loose or tight. See bamboo footies for women.
When the range is still too wide
At the bottom of a range the sock can fold under the foot and press a little. At the top the toe can feel tight and the heel may sit slightly high. That is not a fault, only a result of one pair covering several lengths. See bamboo petticoat.
Leg and foot stretch differently
A leg stretches around ankle and calf, while the foot stretches in length and width. The two parts work together but are not the same. A sock can therefore fit the foot well and still feel slightly loose or tight in the leg. That relates to the shape of the leg, not to a wrong size.
What the wash changes
Socks can shrink a little in the wash, and you may notice it if you sit at the top of a range. Wash as the care label says and avoid high heat in the dryer if you want them to keep their shape. If a sock still feels tight, choose the next range up.
Why some models have more sizes
A few models come in more sizes because support stockings and running socks must fit more precisely. Fit matters more than price there, and the stretch cannot be so large that the sock slips or fails to support where it should. Everyday socks have no such demand, so a few ranges do the job well.
Frequently asked questions
What if I am between two ranges
Pick the lower one if you want the sock to fit snugly, and the higher one if you want to avoid pressure on the toes. Both work, so it mostly depends on how you like a sock to feel.
Do socks shrink in the wash
A little, and you may notice it at the top of a range. Follow the care label and avoid high dryer heat, and the sock keeps its shape and fits as it did the first time you wore it.
Why do a few models still come in more sizes
Because support stockings and running socks must fit more precisely than everyday socks. Fit is part of the function there, so there is no room for the same stretch range as an ordinary sock.
