Is am 6.5 size and could get a 6 however every time I go smaller
I regret it so unless you like your workout shoes a little tighter fit then go half size down.  I am good with the size I picked.  I wear to go to Zumba and kick boxing classes.  They are light and provide good cushion.  This is my 2nd pair of adidas shoes as I like this brand of shoe to workout.