When choosing your size, the most important measurements are the circumference of your ankle and the circumference of your calf. The size of your foot is less important.
Compression is strongest around the ankle and decreases up the leg. Use the size chart shown below the product, to see how your measurements fit into the chart. If you are in between two sizes, you should choose the size that suits the circumference of your ankle the best. It is not unusual that the foot of the stocking is either too large or too small, but you will not notice it once your wear the stockings. However, if the foot size is 3 sizes larger or smaller, than the size you normally use, try stockings with an open toe.