4 sizes for 13″ to 15″ wheels, with the heights and widths their makers list.
Nominal widths from the size code.
6.9 inches wide (175 mm). The 175 only gives the width. Height comes from the rest of the size, so the 4 sizes of this width here run from 22.7″ to 24.0″ tall: 175/65R15 is about 24.0″, 175/65R14 is about 23.0″ and 175/70R14 is about 23.6″.
The size code gives 6.9″. The widths the makers publish for the 9 175 tires here run from 7.0″ to 7.0″. Toyo publishes overall width; BFGoodrich and Michelin publish section width.