Brannock device

The Brannock device is the metal foot-measuring tool invented by Charles Brannock in 1925, manufactured by the Brannock Device Company in Liverpool, NY. Used by virtually every US shoe store. Measures three dimensions: heel-to-toe length, heel-to-ball length (where the arch flexes), and ball width.

US shoe sizes increment in steps of one barleycorn — an English unit equal to ⅓ inch, in use since the 14th century. A US men’s size 10 has a foot length of ~10⅔ inches; each size up adds ⅓ inch. Women’s sizes use the same physical step but are labelled 1.5 numbers higher (a women’s 11.5 is the same foot length as a men’s 10), for historical reasons that no longer have any fitting rationale.

The Brannock device produces accurate foot measurements; the fit of any specific shoe still varies by brand and last shape. Convert any Brannock-derived US size to UK/EU/JP via our shoe size converter.