EUR 40 in US women's is equivalent to a US size 9.5. To determine your exact shoe size, measure your feet and then compare the measurements to the sizes in a chart. Be sure to measure with a Brannock device, which is specifically designed for measuring feet, as it provides the most accurate measurement. Another important factor to consider when selecting a shoe size is the width of your foot. Most US sizes are based on an "M" for Medium width, but some shoes are available in both broader widths (such as W for Wide) and narrower widths (such as AA).
