Originally Posted by *Val*
yes, half a size bigger, 9.5 in nike and 10 in adidas for me (that's in uk anyway)
Yup, I'm a full UK size bigger in Adidas than Nike. (11.5 UK vs 10.5 UK)
In US sizes that is a 12 in adidas and an 11.5 in Nike (only a 1/2 sz difference)
Other people wear the same size in each, usually those with narrower feet (I'm a medium-wide width).