US: 8.5–10.5 to United Kingdom Size 13–14.5
Cross-market men’s sock conversion mapping 8.5–10.5 specifications into 13–14.5.

Analyzing Sock Size Equivalence Across Markets
US: 8.5–10.5: Corresponds to a US shoe size range of 8.5–10.5, foot length of 26.5–28 (10.4–11 ), and fit classification Standard Regular Fit.
United Kingdom Size 13–14.5: Corresponds to a US shoe size range of 13.5–15, foot length of 30.5–32 (12–12.6 ), and fit classification Extended Volume / High Stretch.