US: 3.5–4.5 to Europe Size 35–37
Cross-market women’s sock and hosiery conversion mapping 3.5–4.5 specifications into 35–37.

Analyzing Women’s Sock Size Equivalence Across Markets
US: 3.5–4.5: Corresponds to a foot length range of 20–21.5 (7.9–8.5 ), US shoe size bracket of 3.5–4.5, and fit classification Snug / Petite Fit.
Europe Size 35–37: Corresponds to a foot length range of 21.5–23 (8.5–9.1 ), US shoe size bracket of 5–6.5, and fit classification Comfort Stretch / Ankle Grip.