United Kingdom Size 5-A to US: 5-4A

United Kingdom Size 5-A: Corresponds to a forefoot ball width of 8.4 $\text{cm}$ (3.3 $\text{in}$), ball width range of 8.2–8.6 $\text{cm}$ (3.2–3.4 $\text{in}$), reference foot length of 23 $\text{cm}$ (9.05 $\text{in}$), and fit classification Narrow (7-2A / A).

US: 5-4A: Corresponds to a forefoot ball width of 7.6 $\text{cm}$ (3 $\text{in}$), ball width range of 7.4–7.8 $\text{cm}$ (2.9–3.1 $\text{in}$), reference foot length of 21.9 $\text{cm}$ (8.6 $\text{in}$), and fit classification Extra Narrow (5-4A / Slim).