Running Shoe Size and Fit Conversion Guide
Find running shoe size across US, UK, EU, CM and JP systems with fit advice for toe room, swelling, socks, width and long-distance comfort.
Running shoe fit is more demanding than casual shoe fit because your feet move, swell and absorb impact over time. Start with foot length in centimeters, then compare the equivalent sizes with the Shoe Size Converter. After conversion, check toe room, width and heel lockdown.
Measure After Activity
Feet are often slightly larger later in the day or after walking. Measure then, not first thing in the morning. Stand with weight on both feet and measure heel to longest toe. If one foot is larger, size for the larger foot and adjust the smaller side with lacing or sock thickness.
Leave Toe Room for Movement
Running shoes should allow enough room for toes to expand and move forward, especially on descents. Too little space can cause black toenails, blisters or numbness. Too much space can cause sliding and instability. A thumb-width of front space is a common starting point.
Compare Brand Fit Notes
Different running brands use different lasts. Some fit narrow through the midfoot, others have wider toe boxes. After converting size, read model-specific reviews for notes about length, width and arch feel. For race shoes, trail shoes and daily trainers, fit preferences can differ even within the same brand.