Simcan Socks Sizing:
Small: Women's 5-8, Men's 4-7
Medium: Women's 9-12, Men's 8-11
Large: Women's 13-14, Men's 12-15
EC3D Socks Sizing:
2: Women's 6-8, Men's 6-7
3: Women's 8-10, Men's 7-9
4: Women's 10-12, Men's 9.5-11.5
5: Men's 12+
Smartwool Socks Sizing:
Small: Women's 4-6.5, Men's 3-5.5
Medium: Women's 7-9.5, Men's 6-8.5
Large: Women's 10-12.5, Men's 9-11.5
X-Large: Men's 12-14.5
XX-Large: Men's 15-17.5
Sockwell Socks Sizing:
Women' S-M: US 4-7.5, EU 35-38
Women's M-L: US 8-11, EU 39-43
Men's M-L: US 7-10, EU 39-43
Men's L-XL: US 10.5-13, EU 44-47
Men's XXL: US 14-16, EU 47.5-50