For men’s shoes, a size 42 is equivalent to a size 8 in the British system and a size 9 in the American system. It corresponds to a foot size range of 26.6-27.1cm (10.6-10.7 inches). For women's shoes, a size 42 is equivalent to a size 8.5 in the British system and a size 11 in the American system. In terms of foot measurements, it’s between 27.1-27.7cm (10.7-10.9 inches).