Nike: Manufacturer advice
There is no verified brand-wide fit offset or reproducible wearer distribution in this dataset. Size labels and measured foot length are different quantities. A chart does not establish the fit of every model.
Air Force 1
Nike advises starting half a size below your usual Nike size for the Air Force 1. Its guide allows the usual size for wider feet and distinguishes upper materials and editions. Start with the Nike chart below, then check the exact product and width. Do not subtract another half size automatically from a foot-length chart result: these are two different reference methods.