Why do shoe sizes vary by brand?
EU sizing is consistent across most markets, but US and UK systems use different scales. Brands also apply their own last shapes and fit decisions, so the same foot length can appear as one label in one brand and a half size higher or lower in another.
The tables here are compiled from brand sizing references. For the closest match, measure your foot length in centimeters and use the foot-length option in the converter.
In children's sizing, US numbering resets after 13.5 and starts again at 1 for youth sizes. That is why toddler and big-kid tables are shown separately.