Men's vs. Women's Shoe Size Scales: Why They're Not the Same Numbers
Men's and women's US shoe size scales are offset from each other by a consistent amount — commonly cited as about 1.5 to 2 sizes, meaning a women's size 8 is roughly equivalent to a men's size 6 to 6.5 in actual foot length — a historical scaling convention rather than a difference in how length itself is measured.
This offset is a genuine, useful thing to know, both for converting your own size across a men's/women's version of the same shoe and for understanding unisex sizing.
The approximate conversion
A commonly cited conversion is subtracting roughly 1.5 to 2 from a women's US size to get the equivalent men's US size for the same foot length (a women's 9 ≈ a men's 7 to 7.5) — this is a general guideline, and some brands specify their own precise conversion within this general range.
Why the two scales are offset at all
This offset reflects a historical convention in how the men's and women's size scales were separately established, rather than any fundamental difference in how foot length itself is measured — it's simply a labeling convention difference between the two scales, similar in spirit to why UK and US sizes differ.
Where this matters practically
For a unisex shoe style offered in only one gendered size scale, or for buying a shoe from the "opposite" section as a preference, converting using this offset (or checking the brand's own stated conversion, if provided) helps find the correctly fitting size rather than assuming the number translates directly.