US: 4-6 to Europe Size 15-17
Cross-market children’s socks, tights, hosiery, leg warmers, and dance tights sizing conversion mapping 4-6 specifications into 15-17.

Analyzing Size Equivalence Across Markets
US: 4-6: Corresponds to a foot length of 17.5 (6.9 ), matching US shoe size 10-12, and age range 48–84 months.
Europe Size 15-17: Corresponds to a foot length of 9.5 (3.7 ), matching US shoe size 1-2, and age range 0–6 months.